I had it crash several times a day back when I used to play it

bad luck

also, maybe the fact I've got an HW1 improves stability (I don't know, it's just a suggestion...)
The same way, there are lots of people complaining because they've problems using txtrider... but, on my calc, when launched from the home screen (from an explorer it wasn't exactly the same thing...), it was almost perfectly stable (It sometimes crashed, but really not often...)