Good point; backgrounds seem to be stored in the level .ltb files (I should probably rip these and upload them also), which are WFLZ compressed but after decompressing are in the following wonderful format:
I think these are just map tiles that the rest of the .ltb stitches together entirely (This is my guess, since the paths at the bottom don't repeat).
As for characters and everything else, check out the rip page, it should be everything.
EDIT: Added tilesets to the rip sheets. Looks like they're 16x16 tiles with padding around them, with some larger tiles... I'm not sure if it's really worth the hassle reconstructing the levels entirely, as there's probably tile layers and such. That might also venture from "ripping sprites" to "reconstructing the game" at that point. You can probably reconstruct the levels with a program like Mappy with these images anyway.
I think these are just map tiles that the rest of the .ltb stitches together entirely (This is my guess, since the paths at the bottom don't repeat).
As for characters and everything else, check out the rip page, it should be everything.
EDIT: Added tilesets to the rip sheets. Looks like they're 16x16 tiles with padding around them, with some larger tiles... I'm not sure if it's really worth the hassle reconstructing the levels entirely, as there's probably tile layers and such. That might also venture from "ripping sprites" to "reconstructing the game" at that point. You can probably reconstruct the levels with a program like Mappy with these images anyway.