I think i fixed it.

[CTrooper1]

You know how we where all complaining about the connection being lost? Well i noticed after you log in and you get that page that talks about the serial Numbers and what not. Well by chance when i was fooling with it i had to leave, after i had that page up. So i just left it and came back like two minutes later and clicked custom battle and it kept its connection. If your having the same problem just do what i did and if it doesn't work tell me and ill delete the post.

Hope this helps!