The game shouldn't need SS2Tool, it already has the unofficial patch 2.45 which uses NewDark. The game works nicely for me on Windows 10 x64.

this sound like a bad idea (as the new engine doesn't support win9x), and shouldn't be done, ever - looks like you have some different problem, which we could try to resolve if you are interested.

the windowed mode would be a good start (uncomment force_windowed in cam_ext.cfg).

Well, I had to because otherwise got standard windows crash reporter with an option to send report to M$. So yeah, only in compat mode with win98 it actually works.

Seriously tho, it's very brittle. Not only it needs admin rights (even if its directory isn't in program files and is writable by anyone), but I even have to launch it via shortcuts because when trying to launch via Galaxy... you guessed it, doesn't work and then not even error reporter show up, it just disappears.

Tho, not very important as I don't have much of interest playing it further - beginning was nice, but then it ramps up in speed waaay too fast (nothing compared to "decompressing" segment, because some bomb is supposed to go off or whatever. Too much, too fast imo. If I had bought it, I'd probably returned it, lol.

If you think SS2 gets too fast, something like Doom or Serious Sam would probably make your entire body explode.

If I were you I'd do anything in my power to get it working, it's one of the best games you'll ever play!. You may have to enable or disable a few things in the System Shock 2\cam_ext.cfg" file, just read the documents in the "System Shock 2\doc\" folder first.

No, because in Doom or Sam you just run around killing stuff, here in segment I've mentioned you also have to worry about that bomb or whatever it is. Also Sam/Doom's pacing doesn't ramp up as fast as it does with SS2, so I have time to get used to it.