Multiplayer should work! I built the servers myself haha. I'm not sure if anyone is currently hosting.
As for the crashes and problems I'm not sure. Unfortunately we never got the source code to the direct3d renderer, so there's some annoying issues with certain system configs that make it impossible to get going. I will say Windows 7 is end of life, so I can only say for 10.
And I can't say I've experienced the mouse issue, nor have any of the folks who helped test it. But I'll keep an eye out!
Hopefully you've got it running in the end! It's an old game that needs some love far beyond what I can give it!