I'm running HOMM II under Linux with DOSBOX and it works Just Fine. Alas, I can't get the editor to launch. I try by running dosboxhomm2_editor.conf and it starts OK, but fails when it tries to invoke itself because that's an illegal command. Does anybody know how to correct this?

I've looked at the file and it only tries to launch EDITOR2.EXE, and there's no mention of the config file there.

I think the editor may be a Windows program and thus not launched via DOSBox. But it's years since I played HoMM2, so I may misremember.

If the editor were a Windows program, there wouldn't be a DOSBOX config for it, would there?

EDITOR2.EXE in HOMM2 is the DOS version (just like the game is the DOS version).
So, in windows it is working just fine. It is setup to use the typical dosbox<shortgamename>_single.conf for running most things in DOSBox itself. In windows case, there is no editor conf file. It is a "menu" option in the single.conf file.

Going to the website to see if I could download it and take a look, there is no Linux version listed on GoG for backup installers. And, checking another game that has Linux install (Maniac Mansion), it DOES let me change System, but HOMM2 does not. Did you get this from GoG? Or did you get this from elsewhere or use something like "play.it" to install the GoG version on Linux? I suspect the later. This adds just a bit of complication.

I would need to see the autoexec part of the normal HOMM2 conf file, and the same for the editor conf file to compare and fix whatever is going on.
Or, see what exactly you are clicking on for both to start each. Maybe your shortcut for HOMM2 is fine. But you don't have one really setup for the editor and clicking on something different which is not working.

I bought HOMM2 from GOG, right here. Here's the complete HOMM2.conf file:

# This is the configurationfile for DOSBox 0.74. (Please use the latest version of DOSBox)
# Lines starting with a # are commentlines and are ignored by DOSBox.
# They are used to (briefly) document the effect of each option.

[sdl]
windowresolution=original
fullscreen=true
# fullscreen: Start dosbox directly in fullscreen. (Press ALT-Enter to go back)
# fulldouble: Use double buffering in fullscreen. It can reduce screen flickering, but it can also result in a slow DOSBox.
# fullresolution: What resolution to use for fullscreen: original or fixed size (e.g. 1024x768).
# Using your monitor's native resolution with aspect=true might give the best results.
# If you end up with small window on a large screen, try an output different from surface.
# windowresolution: Scale the window to this size IF the output device supports hardware scaling.
# (output=surface does not!)
# output: What video system to use for output.
# Possible values: surface, overlay, opengl, openglnb, ddraw.
# autolock: Mouse will automatically lock, if you click on the screen. (Press CTRL-F10 to unlock)
# sensitivity: Mouse sensitivity.
# waitonerror: Wait before closing the console if dosbox has an error.
# priority: Priority levels for dosbox. Second entry behind the comma is for when dosbox is not focused/minimized.
# pause is only valid for the second entry.
# Possible values: lowest, lower, normal, higher, highest, pause.
# mapperfile: File used to load/save the key/event mappings from. Resetmapper only works with the defaul value.
# usescancodes: Avoid usage of symkeys, might not work on all operating systems.

fullscreen=true
fulldouble=false
fullresolution=desktop
#windowresolution=1024x768
output=Overlay
autolock=true
sensitivity=110
waitonerror=true
priority=higher,normal
mapperfile=mapper.txt
usescancodes=true

[dosbox]
# language: Select another language file.
# machine: The type of machine tries to emulate.
# Possible values: hercules, cga, tandy, pcjr, ega, vgaonly, svga_s3, svga_et3000, svga_et4000, svga_paradise, vesa_nolfb, vesa_oldvbe.
# captures: Directory where things like wave, midi, screenshot get captured.
# memsize: Amount of memory DOSBox has in megabytes.
# This value is best left at its default to avoid problems with some games,
# though few games might require a higher value.
# There is generally no speed advantage when raising this value.

language=
machine=svga_s3
captures=capture
memsize=16

[render]
# frameskip: How many frames DOSBox skips before drawing one.
# aspect: Do aspect correction, if your output method doesn't support scaling this can slow things down!.
# scaler: Scaler used to enlarge/enhance low resolution modes.
# If 'forced' is appended, then the scaler will be used even if the result might not be desired.
# Possible values: none, normal2x, normal3x, advmame2x, advmame3x, advinterp2x, advinterp3x, hq2x, hq3x, 2xsai, super2xsai, supereagle, tv2x, tv3x, rgb2x, rgb3x, scan2x, scan3x.

frameskip=0
aspect=true
scaler=normal2x

[cpu]
# core: CPU Core used in emulation. auto will switch to dynamic if available and appropriate.
# Possible values: auto, dynamic, normal, simple.
# cputype: CPU Type used in emulation. auto is the fastest choice.
# Possible values: auto, 386, 386_slow, 486_slow, pentium_slow, 386_prefetch.
# cycles: Amount of instructions DOSBox tries to emulate each millisecond.
# Setting this value too high results in sound dropouts and lags.
# Cycles can be set in 3 ways:
# 'auto' tries to guess what a game needs.
# It usually works, but can fail for certain games.
# 'fixed #number' will set a fixed amount of cycles. This is what you usually need if 'auto' fails.
# (Example: fixed 4000).
# 'max' will allocate as much cycles as your computer is able to handle.
#
# Possible values: auto, fixed, max.
# cycleup: Amount of cycles to decrease/increase with keycombo.(CTRL-F11/CTRL-F12)
# cycledown: Setting it lower than 100 will be a percentage.

core=auto
cputype=auto
cycles=max
cycleup=1000
cycledown=1000

[mixer]
# nosound: Enable silent mode, sound is still emulated though.
# rate: Mixer sample rate, setting any device's rate higher than this will probably lower their sound quality.
# Possible values: 44100, 48000, 32000, 22050, 16000, 11025, 8000, 49716.
# blocksize: Mixer block size, larger blocks might help sound stuttering but sound will also be more lagged.
# Possible values: 1024, 2048, 4096, 8192, 512, 256.
# prebuffer: How many milliseconds of data to keep on top of the blocksize.

nosound=false
rate=44100
blocksize=2048
prebuffer=80

[midi]
# mpu401: Type of MPU-401 to emulate.
# Possible values: intelligent, uart, none.
# mididevice: Device that will receive the MIDI data from MPU-401.
# Possible values: default, win32, alsa, oss, coreaudio, coremidi, none.
# midiconfig: Special configuration options for the device driver. This is usually the id of the device you want to use.
# See the README/Manual for more details.

mpu401=intelligent
mididevice=default
midiconfig=

[sblaster]
# sbtype: Type of Soundblaster to emulate. gb is Gameblaster.
# Possible values: sb1, sb2, sbpro1, sbpro2, sb16, gb, none.
# sbbase: The IO address of the soundblaster.
# Possible values: 220, 240, 260, 280, 2a0, 2c0, 2e0, 300.
# irq: The IRQ number of the soundblaster.
# Possible values: 7, 5, 3, 9, 10, 11, 12.
# dma: The DMA number of the soundblaster.
# Possible values: 1, 5, 0, 3, 6, 7.
# hdma: The High DMA number of the soundblaster.
# Possible values: 1, 5, 0, 3, 6, 7.
# sbmixer: Allow the soundblaster mixer to modify the DOSBox mixer.
# oplmode: Type of OPL emulation. On 'auto' the mode is determined by sblaster type. All OPL modes are Adlib-compatible, except for 'cms'.
# Possible values: auto, cms, opl2, dualopl2, opl3, none.
# oplemu: Provider for the OPL emulation. compat might provide better quality (see oplrate as well).
# Possible values: default, compat, fast.
# oplrate: Sample rate of OPL music emulation. Use 49716 for highest quality (set the mixer rate accordingly).
# Possible values: 44100, 49716, 48000, 32000, 22050, 16000, 11025, 8000.

sbtype=sb16
sbbase=220
irq=7
dma=1
hdma=5
sbmixer=true
oplmode=auto
oplemu=default
oplrate=44100

[gus]
# gus: Enable the Gravis Ultrasound emulation.
# gusrate: Sample rate of Ultrasound emulation.
# Possible values: 44100, 48000, 32000, 22050, 16000, 11025, 8000, 49716.
# gusbase: The IO base address of the Gravis Ultrasound.
# Possible values: 240, 220, 260, 280, 2a0, 2c0, 2e0, 300.
# gusirq: The IRQ number of the Gravis Ultrasound.
# Possible values: 5, 3, 7, 9, 10, 11, 12.
# gusdma: The DMA channel of the Gravis Ultrasound.
# Possible values: 3, 0, 1, 5, 6, 7.
# ultradir: Path to Ultrasound directory. In this directory
# there should be a MIDI directory that contains
# the patch files for GUS playback. Patch sets used
# with Timidity should work fine.

gus=false
gusrate=22050
gusbase=240
gusirq=5
gusdma=3
ultradir=C:\ULTRASND

[speaker]
# pcspeaker: Enable PC-Speaker emulation.
# pcrate: Sample rate of the PC-Speaker sound generation.
# Possible values: 44100, 48000, 32000, 22050, 16000, 11025, 8000, 49716.
# tandy: Enable Tandy Sound System emulation. For 'auto', emulation is present only if machine is set to 'tandy'.
# Possible values: auto, on, off.
# tandyrate: Sample rate of the Tandy 3-Voice generation.
# Possible values: 44100, 48000, 32000, 22050, 16000, 11025, 8000, 49716.
# disney: Enable Disney Sound Source emulation. (Covox Voice Master and Speech Thing compatible).

pcspeaker=true
pcrate=22050
tandy=auto
tandyrate=22050
disney=true

[joystick]
# joysticktype: Type of joystick to emulate: auto (default), none,
# 2axis (supports two joysticks),
# 4axis (supports one joystick, first joystick used),
# 4axis_2 (supports one joystick, second joystick used),
# fcs (Thrustmaster), ch (CH Flightstick).
# none disables joystick emulation.
# auto chooses emulation depending on real joystick(s).
# (Remember to reset dosbox's mapperfile if you saved it earlier)
# Possible values: auto, 2axis, 4axis, 4axis_2, fcs, ch, none.
# timed: enable timed intervals for axis. Experiment with this option, if your joystick drifts (away).
# autofire: continuously fires as long as you keep the button pressed.
# swap34: swap the 3rd and the 4th axis. can be useful for certain joysticks.
# buttonwrap: enable button wrapping at the number of emulated buttons.

joysticktype=none
timed=true
autofire=false
swap34=false
buttonwrap=true

[serial]
# serial1: set type of device connected to com port.
# Can be disabled, dummy, modem, nullmodem, directserial.
# Additional parameters must be in the same line in the form of
# parameter:value. Parameter for all types is irq (optional).
# for directserial: realport (required), rxdelay (optional).
# (realport:COM1 realport:ttyS0).
# for modem: listenport (optional).
# for nullmodem: server, rxdelay, txdelay, telnet, usedtr,
# transparent, port, inhsocket (all optional).
# Example: serial1=modem listenport:5000
# Possible values: dummy, disabled, modem, nullmodem, directserial.
# serial2: see serial1
# Possible values: dummy, disabled, modem, nullmodem, directserial.
# serial3: see serial1
# Possible values: dummy, disabled, modem, nullmodem, directserial.
# serial4: see serial1
# Possible values: dummy, disabled, modem, nullmodem, directserial.

serial1=dummy
serial2=dummy
serial3=disabled
serial4=disabled

[dos]
# xms: Enable XMS support.
# ems: Enable EMS support.
# umb: Enable UMB support.
# keyboardlayout: Language code of the keyboard layout (or none).

xms=true
ems=true
umb=true
keyboardlayout=none

[autoexec]

mount c "/home/joe/.wine/drive_c/GOG Games/HoMM 2 Gold"
c:
imgmount d homm2~1.ins -t iso -fs iso
# The next line sets the volume because the internal settings
# don't work for me. May need adjustment.
mixer master 30:30
heroes2
exit

The desktop launcher simply opens that file and runs it. Here's the file for the editor:

[IPX]
Enable=0
Connection=0
ipx=false


[autoexec]
# Lines in this section will be run at startup.

@ECHO OFF
cls
mount C ".."
imgmount d "..\homm2.inst" -t iso -fs iso
c:
cls
EDITOR2.EXE
exit

Hope you can see what's wrong.

By any chance are you the same person in comments here:
https://gamersonlinux.com/forum/threads/heroes-of-might-and-magic-1-2-guide.403/
If so, did you make the shortcut for the editor the same way to the conf file. Because that may be why it is giving a very odd error you mention above.
I can tell you what is wrong in the editor conf file though.
the mount and the imgmount commands are not the same as your normal homm2 conf file.
The editor conf file also does not include all the rest of the DOSBox.conf file settings like the homm2 conf file.
So, you can copy your homm2.conf file into its own editor conf file and simply change the heroes2 to editor2.
And create another "shortcut" using the editor conf file into a Heroes2Editor shortcut.
Or you can modify the current homm2 conf file and make a small menu that lets you choose what you want to run when starting.

Note: this is without fully knowing what you did for the original HOMM2 to start it with a shortcut

Doing its own conf and shortcut for editor:
1) copy the homm2.conf file into a homm2editor.conf file.
2) edit the autoexec part in the new editor conf file and simply change the "heroes2" line under the mixer line to "editor2"
3) create a new shortcut the same way you did with homm2. Or copy that shortcut into another "ex: Heroes2Editor" and edit that file to point to the correct conf file just created for the editor

Adding a menu to your current homm2.conf file:
1) BACKUP current homm2.conf file (ex: homm2.conf.bak) then edit the homm2.conf file
2) change the autoexec from what you have to something like below:
(Note: this adds a menu to your already existing homm2 conf file and lets you play game, choose editor, or run the setup internal to homm2. Also, BACKUP the current homm2.conf file before editing it just so you can return back to how it was before this in case it gets messed up or stops working. Whatever shortcut that references this conf file will work as before and start DOSBox to run HOMM2. Just will be a menu where you hit 1,2,3 or 4 first.

[autoexec]
@ECHO OFF
cls
mount c "/home/joe/.wine/drive_c/GOG Games/HoMM 2 Gold"
c:
goto launcher

:launcher
cls
ECHO º ------------------------------------------- º
ECHO º Heroes of Might and Magic II GOLD Launcher º
ECHO º ------------------------------------------- º
ECHO º 1) Heroes of Might and Magic II GOLD º
ECHO º 2) Map Editor º
ECHO º ------------------------------------------- º
ECHO º 3) Game DOS Settings º
ECHO º ------------------------------------------- º
ECHO º 4) exit program º
ECHO º ------------------------------------------- º

choice /c1234 /s Which program do you want to run? [1-5]: /n
if errorlevel 4 goto exit
if errorlevel 3 goto setup
if errorlevel 2 goto editor
if errorlevel 1 goto game

:game
# CS mount here to avoid music being tagged as CS file
imgmount d homm2~1.ins -t iso -fs iso
cls
heroes2.exe
goto exit

:editor
# CS mount here to avoid music being tagged as CS file
imgmount d homm2~1.ins -t iso -fs iso
cls
EDITOR2.EXE
goto exit

:setup
imgmount d homm2~1.ins -t iso -fs iso
cls
install.exe
goto launcher

:exit
exit

It looks like I'm the same person although I don't remember it. I didn't make the desktop launcher, the install program did, and there's none, as yet, for the editor. I have to use Thunar (my file manager) to go to the proper directory and launch the editor that way. I'm glad you see what's wrong with the editor's config file. Am I right in thinking that all I need to do is change the program's name in the file?

Change this:
mount C ".."
imgmount d "..\homm2.inst" -t iso -fs iso

To this:
mount c "/home/joe/.wine/drive_c/GOG Games/HoMM 2 Gold"
imgmount d homm2~1.ins -t iso -fs iso

in the editor config file.
But, how you start it may be an issue as well.

OK, I'll try that when I can, probably tomorrow.

And, here's the command that the desktop launcher uses:

env WINEPREFIX="/home/joe/.wine" /usr/bin/wine C:\\windows\\command\\start.exe /Unix /home/joe/.wine/dosdevices/c:/users/Public/Desktop/Heroes\ of\ Might\ and\ Magic\ 2\ Gold.lnk