Really impressive system, I know getting multiplayer working in any form is not easy!
Yeah have to agree with the above, it's very hard to make anything clever with the way the joints work. Rotations don't seem to translate into the game. And on top of that, it's very unbalanced, there's so many ways to cheese the system. I think I have found an unbeatable strategy :P
Besides that, it's a really cool base and I hope you flesh out the building system because it's really fun!