Grasshopper, you are going to have to learn patience. :meditation:
Have you considered Plastilina clay? It's oil based, so no moisture and no need for mold release. And it's softer and easier to sculpt...just make sure it's sulphur-free. It's what I use. Unlike Theobromine, I prefer hard resin molds, but she's having great success with urethane rubber molds.