I'm trying to create a custom overlay for my map, I saved it as a .tga and placed it in an overlays folder within my materialsrc folder, the problem is every time I drag it to the vtex icon and the dos prompt comes up it states the .tga is bogus, the developer wiki says "The texture image you are trying to convert is not recognized as a valid targa (.tga) file. Make sure that it is, and that it is either 24 bit/pixel or 32 bit/pixel. (16 bit/pixel is not recognized.)" How would I check this?