Spawning inside walls only happens when loading maps other than the ones supplied with the mod. Since those are lacking the required team starts, the players will spawn at 0,0,0 which in many stock maps is outside the actual level.
As for the push issue, I realize my clip hotfix wouldn't have worked at all as the balls bump off clip walls, too. I made the trigger volumes a bit bigger now, 16 units wide (and also replaced the non-QRP textures except for metal4_2b). Though I'm sceptical the wider triggers will solve the issue (which I believe to be related to either some network protocol/ping thing, or some maxfps-type of config messing). Anyway, might be worth a try:
Edit: As an afterthought, could it be related to that issue where a trigger_hurt in a space map doesn't kill a player if it has fired shortly before (by another player)? So in this case, if two players touch the push at the same time. Clutching at straws here obviously.