I have no direct suggestions, but maybe contact Sugar Flair and ask their advice. After all, it is their product.
Hello to spray gold paint with an airbush you first have to sift the gold paint through a nylon stocking and then you can airbrush with it.
I would recommend shaking the airbrush really well, I have the issue with metallic airbrush. I microwaved some liquid in a shot glass for a few seconds to soften any hardened stuff.
Hello Diane, I dont like change de needle, with 0.2 you have more than enough to work with any color. Most important is the material you use to paint. I use glitter but not this brand, so maybe can be the product. In most of the cases depends the quantity of alcohol and colour you mixt, you should even be able to paint over chocolate. :-)