Help: Makeup over prosthetics

Warning: New to all of this...

I'm trying to do makeup effects to make a zebra, and I already have a foam latex prosthetic that I have sealed and I have RMG, which I have applied already to pre-paint the prosthetic, but it is VERY tacky and cannot be thinned to paint stripes.

My question is, can I use alcohol-based paint such as Skin Illustrator to paint OVER the RMG? If not, is there a way to thin the RMG to make bold brushstrokes instead of spreading this tacky substance?

Typically you do not use RMG to pre-paint a prosthetic appliance. The grease paint is a make-up and will never stop moving around. I would suggest pre-painting the appliance with PAX Paint. You can buy it directly from Make-up & Effects Labs or you can make your own. If you decide to make your own, you will need Pros-aide no-tac adhesive and acrylic paint. The PAX paint will dry and stick to the prosthetic and it will remain a little stretchy so that it does not affect the movement of the prosthetic. When you apply the prosthetic that is when you can use the RMG and/or alcohol based make-ups like Skin Illustrator.