Have to use novert and add it to the single config file (maybe to all cfg files of the corresponding game), it works fine.
Also reconfigure keys in the dosbox mapper. Mine is like this (I give it all because I odnt remember what was changed exactly, was long ago). Copy it to the mapper. Normal WASD movement + fast turn bound on Shift and normal keys for nukes:
hand_shutdown "key 290 mod1"
hand_capmouse "key 291 mod1"
hand_fullscr "key 13 mod2"
hand_pause "key 19 mod2"
hand_mapper "key 282 mod1"
hand_speedlock "key 293 mod2"
hand_recwave "key 287 mod1"
hand_caprawmidi "key 289 mod1 mod2"
hand_scrshot "key 286 mod1" "key 8"
hand_video "key 286 mod1 mod2"
hand_decfskip "key 288 mod1"
hand_incfskip "key 289 mod1"
hand_cycledown "key 292 mod1"
hand_cycleup "key 293 mod1"
hand_caprawopl "key 288 mod1 mod2"
hand_swapimg "key 285 mod1"
key_esc "key 27"
key_f1 "key 282"
key_f2 "key 283"
key_f3 "key 284"
key_f4 "key 285"
key_f5 "key 286"
key_f6 "key 287"
key_f7 "key 288"
key_f8 "key 289"
key_f9 "key 290"
key_f10 "key 291"
key_f11 "key 292"
key_f12 "key 293"
key_grave "key 96"
key_1 "key 49"
key_2 "key 50"
key_3 "key 51"
key_4 "key 52"
key_5 "key 53"
key_6 "key 54"
key_7 "key 55"
key_8 "key 56"
key_9 "key 57"
key_0 "key 48"
key_minus "key 45"
key_equals "key 61"
key_bspace "key 8"
key_tab "key 304"
key_q "key 113"
key_w "key 119"
key_e "key 101"
key_r "key 114"
key_t "key 116"
key_y "key 121"
key_u "key 117"
key_i "key 105"
key_o "key 111"
key_p "key 112"
key_lbracket "key 91"
key_rbracket "key 93"
key_enter "key 13"
key_capslock "key 301"
key_a "key 97"
key_s "key 115"
key_d "key 100"
key_f "key 102"
key_g "key 103"
key_h "key 104"
key_j "key 106"
key_k "key 107"
key_l "key 108"
key_semicolon "key 59"
key_quote "key 39"
key_backslash "key 92"
key_lshift "key 304"
key_lessthan "key 60"
key_z "key 101"
key_x "key 113"
key_c "key 99"
key_v "key 118"
key_b "key 98"
key_n "key 110"
key_m "key 109"
key_comma "key 44"
key_period "key 46"
key_slash "key 47"
key_rshift "key 303"
key_lctrl "key 306"
key_lalt "key 308"
key_space "key 32" "key 301"
key_ralt "key 307"
key_rctrl "key 305"
key_printscreen "key 316"
key_scrolllock "key 302"
key_pause "key 19"
key_insert "key 277"
key_home "key 278"
key_pageup "key 280"
key_delete "key 127"
key_end "key 279"
key_pagedown "key 281"
key_up "key 119"
key_left "key 97"
key_down "key 115"
key_right "key 100"
key_numlock "key 300"
key_kp_divide "key 267"
key_kp_multiply "key 268"
key_kp_minus "key 269"
key_kp_7 "key 263"
key_kp_8 "key 264"
key_kp_9 "key 265"
key_kp_plus "key 270"
key_kp_4 "key 260"
key_kp_5 "key 261"
key_kp_6 "key 262"
key_kp_1 "key 257"
key_kp_2 "key 258"
key_kp_3 "key 259"
key_kp_enter "key 271"
key_kp_0 "key 256"
key_kp_period "key 266"
jbutton_0_0
jbutton_0_1
jaxis_0_1-
jaxis_0_1+
jaxis_0_0-
jaxis_0_0+
jbutton_0_2
jbutton_0_3
jbutton_1_0
jbutton_1_1
jaxis_0_2-
jaxis_0_2+
jaxis_0_3-
jaxis_0_3+
jaxis_1_0-
jaxis_1_0+
jaxis_1_1-
jaxis_1_1+
jbutton_0_4
jbutton_0_5
jhat_0_0_0
jhat_0_0_3
jhat_0_0_2
jhat_0_0_1
mod_1 "key 306" "key 305"
mod_2 "key 308" "key 307"
mod_3

Just so you know, there is another Catacombs port currently in the works, so that should also be an option in the future:

https://www.doomworld.com/forum/topic/102331-catacombgl-a-windows-source-port-for-the-catacomb-abyss/

I know about CatacombsGL and I'm already using it for The Abyss. The fact that there haven't been any updates over the last months (not even any news about the current state) makes me believe that it's already dead though. :(

Take a look at the Doomworld thread again...

Good to see this is not dead as this is a much better source port than Reflection Keen. I'm looking forward to trying the new version when available.

Another alternative is to use my build, DOSBox ECE. There you can turn off the X and Y axis off the mouse separately, so if you set the sensitivity for the Y axis to 0, you effectively turn off the forward and backward movement.

dosboxece.yesterplay.net

Arno just released version 0.2.0 of CatacombGL!

This new release features some significant improvements, such as:

Support for the Catacomb Armageddon! All levels and monsters are present. Requires the Catacombs Pack from GOG.com.
Game selection screen with the option to manually browse to a folder with game data. Suggested by @Master O.
Support for x64 builds. Implemented by Arsen "Honeybunch" Tufankjian.
Support for full screen and borderless windowed mode.
In game help screens. Accessible via the F1 key.
Customizable player turn speed. Suggested by @doomjedi.
Customizable player run button. By default, the run button is not bound to any key, since the original games did not support running. Suggested by doomjedi and Tricob.
Enjoy! And as always, please let me know if you encounter any bugs or have some suggestions for improvements.