If your error is something along the lines of "Runtime assert: modules in Common.cpp (176)", then I'm getting the same on the newest SDK revision. That's the error message on Linux, but the Windows one is something like "Assertion Failed! Version 785 File Common.cpp (176) modules" - anyway, it seems to have the same problem however you run it.
I'm not 100% certain, but I think it's simply a bug in the SDK, i.e. revision 785 does not work/the newest version is broken.
The other option is that it won't run anything on it's own, but needs some extra files and configuration to work (perhaps something in the Modules folder, as it mentions modules?). I don't know how to set those up, sorry. For more information on that, your best bet would be checking on Fonline.ru (with google translate if you don't speak Russian).
A previous revision must be working, but I've not done enough testing to find how far back to go to find a working one. The revision history (in English) is available here :
https://xp-dev.com/sc/history/76003/HEAD/%2FBinaries%2FServer?page=0One useful point is that build 604/605ish (from April 2016) is the last one which bundled all the TLA (The Life After) modules with it - so that's quests, Fallout characters, scenery, scripts, interface, objects etc - so that may be most useful for getting something up and running quickly, and learning by reading the scripts.
Soon after build 605ish, they separated the core FOnline engine from the TLA module - so the newest SDK contains the engine, but not the scripts/Fallout/FOnline stuff (they're separately available from
https://github.com/cvet/fonline_tla).
For prebuilt snapshots, there's a few around on the forums - I think the one in Raynor009's thread here :
FOnline SDK (non repository, direct download link) is the newest one that's ready to go, at Revision 535 (which is a few years old now) - someone else may be able to advise on a better one that's available.
For the fine details of setting up the server, you should be able to read through some tutorials on this forum - it's not my area of speciality unfortunately - but someone will be able to help you.
Hope that all makes sense, and good luck!