[CocoaSpud]

The combat icons can be as large as you want, as long as they are an even multiple of 48 pixels in both directions. When I was testing this last year, I used a dragon icon that was 8x8 squares (8x48=384 pixels across). Although there is no enforced limit on icon size, the 8x8 icon used up most of the screen.

DC supports multiple image formats. Some have side-by-side walls, while the oldest format has walls scattered around. You can use a different format in every slot, but all of the art in a single slot must be the same format.

EasyTex is about the best tool we have at the moment for creating new walls. Which mode were you using when some of the walls didn't line up correctly? (640, 800, 1024)