Tony;
I usually use the "sparkle paint" for most things. I've made sheets down to the thickness, so thin, that they unfortunately were "too thin" and I couldn't use them without them tearing. (about the thickness of tying paper, way too thin, for my use!).
I speed up the drying by setting the glass sheet under a 100watt light bulb, usually, or if in no hurry just let it "air dry" overnight. (the light bulb's in a clip on lamp and about 12" above the piece of glass)