A brief search for that product turned up nothing. Maybe you can provide a link so someone can better assist you.

FWIW, I use Devcon 10110 properly proportioned using a gram scale, and KIWI brand natural color shoe polish as a mold release. I pre-warm the project and keep it warm during cure. 80 F is a good starting point.

In my experience, a putty type epoxy is good in many situations, just not this one. You'll need to roughen the composite surface by sanding to get good adherence and clean thoroughly with acetone or lacquer thinner.

Good luck, and let us know how it turned out.