Critters... or attack peasnts\peons (lloks like normal ones)?
Since this thread is updated, i do an answer i want to put here long ago.
Back in the not so much old days - there is FPT server from Blizzard. Although for last 10 year it been avaialbe (its still but only by direct links to files\patches\game downlaoders) actually as HTTP.
So anpother 10 years back it bean real FTP. And about 20 years ago you dont need Google Drive applications to upload something to "cloud" and else Web2.0(*) features. Cool staff, right? No, we miss something been simple.
Go to your normal Windows Explorer - just open some folder - tap in FTP:xxx.xxx.xx/ adress and you be able to put something from your PC to this network shared folder.
So FTP have one location avaialbe to free access and upload some files. After that it merge to another location, where you can only download them (while dir-location require passwrod or 403 error - like current HTTP://ftp blizzard com/).
Not supre about Win8 and 10, never do something like that, but Win7 is still left some sort of it. In very old days you dont need even Netscape, it work exactly like current "shared network folders" right from normal Windows Explorer. Not access to webadress from Explorer will start WIE oe Windows Egde (probably).
Something like that.
There is 180th file in archive (GOG mistaken describe acrhive as 180 community maps while it only 179) - readme file. This files been part of that one free acces and one restricted acces FTP directiroes. You open this file, see insctruction and copy-paste your zip archive from local folder to FTP folder. It already can be downlaoded from others, but later moved to mdoerate location.
Its not the fact that Blizzard will lok at what "in the box". Its not specific for Blizzard and FTP servers. Some devs also take any maps you send them.
Some CHOOSEN and really tested maps by Blizzard are stored on
http://classic.battle.net/war2 .
So non Blizzard non GOG test what in the archives (and most maps for some else developers and other games - its just sharing storage from dev). There is a high chance that most of the 179 maps are not properly worked or not properly worked on Bnet2.02 version. No one test them.
For some else not-so old DOS\Win3x\Win9x games it be mailto way to upload your maps. It still not mean devs will test them.