Good stuff so far
Im not promising anything, but mind giving an overview in regards to how many colors you're using, and how you're using them please? Also, are the graphics downscaled in size?
Basically Im just after whatever info a person would need to know if they were to have a try at helpng with some graphics?
I've got a fair bit of experience with downscaling color depth. The following is an (incomplete) attempt at a mock up of SF2 I did a while back. Uses 30 colors, but 16 are "locked in" for the character "sprtes", so only 16 unique colors per backdrop (still have 1 undefined in this mockup).
http://oi43.tinypic.com/2quoqae.jpg
As I mentioned I wont promise anything, but currently Im interested in having a play to see what sort of results I can get, I just need to know what restrictions are in place.