Modular Combat is currently broken because Valve changed the data file format and the mod doesn't know how to use the new format. The issue will be fixed once Archer (Lead Developer) finds time to fix it.
We do not have an ETA of when a fix will be made. But when one is made i will put up a server for the mod again.
This is a really good mod and those are bad news.
Yeah unfortunately you not the only mod having this problem :/
Silly Gabe.
I hope you fix it soon, it´s really great modification to play with friends :)