program != process (window)
This distinction is important, as originally Chobby was also one program, but had two different processes: one for the game, and the other for the lobby. Then we had a
long discussion, and decided to go for single process instead.
Both approaches have pros and cons, and the thing you mentioned (Spring crash taking Chobby with it) was one of them. The other cons are performance issues (single threaded Lua) and lack of multi engine support. If you go for the alternative (two processes), which a lot of people don't seem to like (e.g.
Shadowfury333 and
hokomoko were pretty vocal about it) then you have to implement some sort of inter-process communication, which isn't trivial, but still doable (patches supporting both single and two-process Chobby are welcome).