Is there a good technique to stitch together multiple animation poses from the library?

As an example, I just got the Wyvern motions from DAZ (very good, BTW). There is a library animation for taking off, and another for cyclic flying. I wanted to combine these. I can load the take-off item first, increase the total frames and load the flying item at the end of the take off pose. The problem is the location of the Wyvern is different between the two library items. So he takes off, but then jumps back to the start (origin?) when he begins the flying cycle.

Thanks!

Dan