I bought the molds at michaels, they are for cakes but I can't fill them properly, they get all sticky and the figurine comes out really bad, I tried to use the powder sugar or the corn stratch but the molds still don't work properly is it ok to use shortening instead of the powder stuff????

I had a proble like this, and it turned out my fondant was to soft. I used a stiffer fondant, and it worked like a dream. Maybe you could try that with the cornstarch.

I just did a Ratt with black mmf (in my photos) and did not use anything for sticking...it came out perfectly. the fondant was stiffer, as I had added cocoa along w/ the black food color, and it popped right out. GOOD LUCK!