The area that the bowser boss appears in,
if I modify it at all, like adding a new enemy sprite or something, it seems that the game crashes when I enter that area. Are we unable to modify the boss rooms, or is there some workaround for this?

Edit: on closer inspection, it seems that some stuff works, and some doesnt. It looks like just enabling certain sprite sets, such as 3-1 will cause the area to crash.

Of course you can edit it, but sometime it fails.
In my case I only get errors when I change BG.

You just need to change a bit--->test--->change more--->test again--->until you get it works.
Oh, don't forget backup, they're important

P.S.About sprites sets...maybe the game doesn't allows you to use those sprite when bossfight.

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