Hmmm, playing around again...
I really hate setting non-real world / unrealistic configurations but it seems you need to with this game in order to see more.
It seems the game keeps stacking files into memory after each stage and doesn't clear the last stage's...
So, set 8MB Chip RAM and now I see the "Ape" stage followed by another "Dragon" stage:
...before the game crashes saying not enough Fast RAM:
If I try combinations of Chip & Fast RAM however, I can't get it to load the "Ape" stage before crashing...
Maybe someone can work the sweet RAM settings.