Clyde -
I understand your frustration, having had similar frustrations when I first started to create skins. FWIW, there are a bunch of links to tutorial articles on the Wincustomize home page. But it is fair to say that there is much about WB that can only be learned through trial and error. I have to admit that I wouldn't want to have to write the user manual either, but there is so much about creating skins that is counterintuitive or inconsistent from element to element that a really detailed reference sure would be nice.
I think one thing that could be done relatively easily would be to flesh out the little Help Tab in SKS (the lower left pane), with a little more information, such as the orientation of the tiles (vertical vs. horizontal) and specific image size information for those elements that require images of a fixed size. It seems to me a lot of toe-stubbing could be avoided relatively easily, though I must admit that template images are provided.
The Template method is actually very useful for creating images, but until you stumble across how to use it, you don't know; you highlight an element in the Explorer pane and then click on the Template Tab in the Preview Window and a template image for that element is imported & you can then edit that image or use it for obtaining dimension information.
Frustration comes with skinning, but at least there is a community of skinners hanging out, willing to help each other learn the ropes through forums like this. Hang in there, and keep skinning.
Cheers,
Daiwa