(Modified from my original post)
I am using OpenTK's TexLib for my texture loading (http://www.opentk.com/project/TexLib). Never had any trouble with it.
I am experiencing a weird issue. When I compile my application to an exe and run it, textures of any shape and size work just fine. Renaming the exe to an "scr" extension (to make it a screensaver) works perfectly fine on most machines, but on a handful of PCs, the textures fail to load unless their dimensions are exactly powers of 2. (32,64,128,256, etc.) But the problem only exists when running as a screensaver. If I rename the screensaver to an exe, the textures load fine, regardless of size.
Why would the application being run as an screensaver cause this strange behavior? Any ideas on how I can circumvent this issue? My screensaver allows user uploaded textures so I'd rather not mandate a "powers of 2" requirement on the texture dimensions.