I
loved what I was able to get through in Crossover, but that experience didn't even make it to the 3rd boss before it broke.
I've heard the same about the latter games too. Shame. It's an incredibly beautiful game.
One thing I do like about the level concept is that you can't play the hardest one until you've finished the second-hardest one. With games generally giving 5 levels of play-through from
Easy, Normal, Hard, Fuck You & Death, Forever I'll always start on
Fuck You, and if I like it enough go back and play through at the hardest level. This is one of the few games that gives you reason for that.