Check SDK maps and maybe ask on
fonline.ru if someone recreated map(s) you're looking for using fonline mapper.
If not, well... only known way to "convert" maps from original is: get dims mapper, get
all fonline mapper (and client!) versions, open map, save, open in newer version, save, open in newer version (...) and so on, until you reach current SDK mapper version. Tried that few months ago on
Arroyo Bridge map, and - with few minor issues - was able to run it without problems. Took some time but oh well
Problem is, that you will need really, really,
really old stuff for that, older than public SDK and even 2238 itself. AFAIK only person who can give you access to such old tools is cvet.