The problem was, if you were in a time trial and quit, it wouldn't go
back to selecting your current time trial. But also if you were in a
custom level and quit, you would still be on the playerworlds menu.
The problem was twofold: first, I simply wasn't doing the custommode
check. But secondly, I couldn't use map.custommode directly, because
whenever you quit the game aggressively hardreset()s everything
immediately when you press ACTION.
There's probably a good reason for that aggressive hardreset(), so I
won't touch that hardreset() in any way. Instead, I had to introduce two
kludge variables wasintimetrial and wasincustommode to Game, and use
those to do the check proper.