Bah. I lost my post so I have to retype it now. Please forgiven my bluntness.
You can't make a nonUI mod to use skins. You can however move files around to have the same effect. It is bothersome if you haven't copied and manipulated files, but to someone comfortable with the file system it is easy.
Hmm, I thought my instructions were pretty clear (otherwise I would have changed them). What about them wasn't clear? I'd like to change them so they are very understandable and readable.
Lifekatana's instructions are good enough if you have already used a skin replacement. If you haven't though, they aren't very clear. You might consider checking out my instructions in one of my skin threads. Furthermore, this isn't a UImod. It is a skin replacement. If you don't warn people they might overwrite their original rook files and be unable to put them back. This may make some people very unhappy.
I tried to download your skin a couple of times and it was causing FireFox to crash. I'm not sure if it is the ads or what.
Initial Post's Rook Graphic
Very pretty. Very nice. Lots of good work. Why is it in 100x600 slices?
It is over 2 meg in size. You'll be better served by making it smaller. It uses up less bandwith and is easier to deal with. To see what is going on you don't need such a large image.
re: Rook Skin
Given my own work with skins, I know that it takes a troublesome amount of time to complete. Looking at how complicated the rook is and how nicely you recolored everything, I have no doubt that you spent 20 hours fixing it up. It looks very nice. Congratulations on your first skin.
re: Rook Skin File size
The file is uncompressed and too large (over 20 megs). For the base albedo.dds files GPG used BC1/DXT1 compression. I would suggest using it as well. It will shrink your file size by a factor of 10 (i.e., make it 2 meg).
re: Skin appearance
I tried out your skin (the 21 meg uncompressed version and a different compressed version). You want to be careful when it comes to areas that are covered by team color (see the *_specTeam.dds file). Those areas will be overwritten when Team Colors are on (default hotkey F12). Also, for some reason, the textures on my Rook in game weren't nearly as clear as the textures in your pictures. Any ideas why? I do have a relatively low tech graphics cards (256 megs, dx10 compatible, etc), but I wouldn't think it would be that bad. The following graphic displays both the team colors (compare left to right), and the skins (It is currently set to high visual settings).