Is there a way to change background in the special stages from Sonic 1? I do need it in my hack and I have no clue for what I can do. Thanks.
First off, simple questions go here: http://sonicresearch.org/forums/index.php?/topic/1335-basic-questions-and-answers-thread/ Second of all, try using SonMapED or Flex.
I don't have access to the code at the moment (or a computer) but iirc, the code is handled by a routine called ss_bgload, where the clouds are loaded and the mappings for the birds are wrote 8 tiles by 8 tiles, and interlaced. If you want to get a new bg, you will need to remove the code that loads the mappings for the birds and fish, then you will be left with the ssbg2 stuff, which you can replace by loading your art to vram and loading the mappings for the bg. I'd like to be more specific, but I have no access to the code, so I can't help you that much.