Project X is a can of worms on its own, and using it on newer operating system is only asking for more issues.
There's a
windowed mode compatible with v3.6.31.0, that comes with a bunch of compatibility options on its own. On my machine windowed mode's default configuration fails to bring frontend back after finishing a round, the same issue I've seen brought up on forums. Setting
UseDirect3D to
0 in
wndmode.ini fixed it. Setting
UseDDrawEmulate to
1 speeded up the frontend even further (but I have no idea how any of that works and what it might conflict with). I don't know how much of this would apply to your case.
If nothing helps, might have to live with laggy menus.
By the way, RubberWorm still works on 3.7.2.1, you'd just need a
newer version of the module.