This happened twice to me today. The first time was in egyptremix, and after a few minutes, a message came up and said "Incorrect Server Protocol Version".
The second time it happened, it was in mrbelowfloor, I think, and after a few seconds, the game closed and I found this error in my gg2 folder:
ERROR in
action number 1
of Begin Step Event
for object Client:
In script ClientBeginStep:
In script doEventScoreIntel:
Error in code at line 13:
instance_create(IntelligenceBaseRed.x, IntelligenceBaseRed.y, IntelligenceRed);
at position 42: Unknown variable x
Here's a screenshot to show how it looked like:
