~/tg-station/_maps$ ls
RandomZLevels map_files metastation.dm ministation.dm tgstation2.dm
i have those files available as maps, tgstation2.dm is the one presently compiled in
i don't know how to change them, or edit them (yeah yeah use dream maker - i haven't got it installed.) so if i was to change the map to ministation, i would just rename "ministation.dm" to "tgstation2.dm" (after backing up tgstation)
i can't actually test to make sure it all worked correctly, and i have no idea what the map looks like
if you guys are interested, i can try swapping the maps out