Thanks for the input Defiler -- it's much appreciated. 
1. Masking tape allowed me to cut the shapes I wanted more precisely. If that airbrush thing I posted works as I hope it does, paint bleed shouldn't be an issue. If it is an issue then it's on to plan B: liquid masking.
2. If it's not gold, then what is the shiny yellowish color in this picture:

It's more pronounced in this shot than in some others, I'll admit, but there's some kind of yellowy color there...isn't there?
3. I tried a couple types of masking tape and used the one with the most stick to it. I'm positive it was due to excessive paint.
4. I'm not sure if it's that I don't have patience, or if it's just that I love working on Star Wars costumes so much that my addiction prevents me from walking away when I should. 
Cheers!
TJ