uxtheme.dll is a file in windows xp that verifies that your visual styles have microsofts digital signature. Of course all the cool ones dont. So basically what windowblinds and style xp do is hack this dll and make it so you dont need a digital signature to set themes. Downloading this dll by itself will let you skin scrollbars, windows etc without having to install style xp or windowblinds. Ive only been able to get it to work with style xp themes which is great and theres no resource loss at all. Do a google search and you can probably learn even more.