Now that is strange...try waiting it out. Also, what version of map?
might be the longer than usual loading times that makes ppl alt-f4 instead of waiting? That always happens to me, always at least one who leaves the start of the game.
2 times I got gas instead of an random element, in -ar on on lvl 15 and 30 I think, when looking at the replay the game crashed ;/ attaching the replay. ingame nick ixzidor.
Element Tower Defense random bug.SC2Replay