Cant open your capx because you use C2 beta. But I think that you need to create variable and than set this variable to YourObject.AnimationFrame to save what frame is showing now, to stop animation on frame you just need to set animation speed to 0 and then to set animation frame to desired, to set animation frame to what is saved in variable - you need to set frame and just type variable name.
Hope this will help.
actually object has 6 instances and all instances has frames