I entered animation, chosen snapshot and proceeded by clicking on Body defination and set it into one part per body, but when started to drag objects i'm getting an error "The mechanism constraints could not be satisfied. The mechanism could not be assembled"
This is common. I'd recommend a careful review of your constraints. You may also have a condition where you are not returned to a regenerated state. I find this seriously annoying but it happens. Snapshots are suppose to be the answer, but first you need a robust assembly properly constrained.
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