I have definitely filled in part that were left off. I haven't had any trouble at all. The only thing that I do is make entirely too much and waste it! I use craft sticks to stir mine when I make a batch. I keep Dixie cups here to mix it in and when I want to make a very small batch I cut the cup down to about 1/4" from the bottom and stick a craft stick into each of the 2 parts and gauge how much you are using and mix in the small cup. I use a long pointed tool - you could use a tooth pick if necessary - and fill in the holes that are missing; let dry and it should be okay. I love this stuff. I make jewelry and pour it over the jewelry to give a cloissine (sp) or fired effect.

Thanks Nonnie ! This is the ONE time I didn't mix enough ~~~
and it's on a very fancy mosaic piece. *sigh*.... I'll try the 'fill in' method now !