I'll post more as I look over your WPS, but:
%x|a|RockBoxWPSd.bmp|0|0|
displays RockBoxWPSd.bmp, and then
%xl|a|artist.bmp|0|16|
Tries to load a bitmap into the same "a" variable. That's a no-no. also, while I don't know if it's required, generally people do all the loading of images FIRST, before any WPS code.
***EDIT***
Also, you don't have a %xl|g| anywhere, so how is your %xdg supposed to load it?
That should take care of both of those red hilights.
***EDIT***
While we're at it, is RockBoxWPSd.bmp a fullscreen bitmap for your background? If so, you should be using:
%X|RockBoxWPSd.bmp|
to display it.
Also, with static images, assuming you have a background image you should put them into it (acutally paste them into the image in your image editing software). This will save memory for your music, meaning less HDD accesses and longer battery life.
*** EDIT ***
This post is like 11 days old, why am I putting so much time into replying to it? I got tricked by a 'new' tag!