Keep getting awful cracks!!!

Have tried rolling fondant at different thickness, have used water, piping gel & BC to 'glue' fondant to dummy, why do I keep getting those cracks after fondant dries???

Any suggestions to solve this problem?

I don't know if this will help, but I usually grease my dummies with shortening.

 only rub a tiny film of shortening on my dummies too. Then it just peels off with trouble, or you can whack it with a rolling pin or mallet, rather than soak it in water, and other messy things.

Not sure if the dummy is your trouble though. The fondant shouldn't behave any differently than a real cake once it's on there.