Shy Guy: 60 standard GRPs would only occupy around 32MB of SD Card space. Sure, you can't fit that all in memory (especially since GRPs are half the size when saved) but that's nowhere near 2GB.
This still doesn't explain how you made two programs run at once. You must've just edited the game and put a fake launcher wrapper, there's no other way.
I'm not supporting this until I get a proper explanation. How did you manage two programs to run at once? Surely you just modified your copy of PetitWorld and added some frame-capture routine. Not buying it :P
you can make BG layers bigger than 3600 tiles (in fact, the limit is 16383), but the internal renderer can only display a maximum of 3600 tiles on screen at one time.
Hehe, I accidentally made a weird inverse function 1/(1-ROW%/239). Not sure what I was trying to do there, but at least it accidentally turned out cool! It would make an EXCELLENT text scroller.
Play Coin spending DIALOG. By doing it through DIALOG, we can force the user to confirm that they want to actually spend their play coins, so malicious code that drains them all won't get by. Also, potentially a way to check how many play coins are on the user's 3DS.
Play Coins are such an underused feature of the 3DS and I don't want my 300 to go to waste :P.
I didn't actually notice it was fullscreen in your original. I just wanted to see how small I could make one of these. It could be a /little/ smaller, but it wouldn't quite be the same.