I use Bootskin myself, both on my Windows 2000 PC and Windows XP Pro, each with no problems at all. The only thing with Windows 2000 is that the progress bar doesn't grow as normal, it kinda shifts back an forth, other then that, its working fine. Would like to see this fixed in the next version.
As for creating my own Bootskin, here is what I have come across. I tried using Paint Shop pro, brought the picture down to 16colors(4bit), 640x480 and all looks like inside Bootskin, but when I go to load it, windows changes the colors. Either making it very dark, or mostly white, depending on the image. This is without creating a progress bar(yet). I tried the exact same picture using FotoCanvas(or whatever its called from ACD systems) and did the same thing, and now the picture looks as it should. Would like to know what FotoCanvas does, that I am unable to duplicate in Paint Shop Pro. I know that wen I create the progress bar, it should be a certain size and needs to be the same color palet as the background. If anyone has created/edited a picture in Paint Shop pro and it came out okay, please let me know what dithering type to use, since there is a couple types of dithering to use.