I have 11 sliced sprites in layers, a book for the player interface, 2 for the spine, 5 for pages, and 2 for the front cover inside and out, 500 wide and 600 tall. 2 for the back cover inside and out, they I believe the LOVE to HATE me, by messing with my patience. the outside panel tends to render in infront of the inside half the time. Anything special I need to consider...
Oh minor suggestion when setting up sprite slicing or anything with manipulating the vertices.. they are a pain in the ass to grab, I find myself clicking 2.... 3.... 4 time to get them to move, Maybe increase the collision detection somehow... ?