I've been trying to figure out if this is possible.  So far, it doesn't seem to be.

I have one animation where I want to add about 20 frames at the beginning-a little "anticipation" action-and another where I want to delete the first 29 frames.  Poser doesn't seem to allow you to add or delete frames except at the end of an animation.  Can anyone tell me how to do this?

Thanks.