Not sure if you are still looking for an answer to this (you have probably figured it out already), but...

We transplanted 5 "runners" this past spring. They traveled for 1 1/2 hours in the back of a pickup with a little bit of moist soil covering the roots. Oh, and we had them laying kinda on their sides. Anyway, when we got them home, there were 2 of them that looked like they weren't going to survive, but I planted them anyway, thinking it wouldn't hurt anything to try. Everyone of the plants made it. As a matter of fact, the one that looked the worst is doing the best! lol Crapes tend to be pretty hardy...

Good luck keeping it on the small side! lol From all my experience with them, it doesn't matter when or how much you prune, they'll be full size by the end of the growing season! Hubby's grandmother whacks hers nearly to the ground every fall, and they are 6 feet or more by the time the next fall rolls around! You can prune them just about year around. I had one that sprang up around an oak tree that I couldn't keep cut back. And don't forget that they are "runners"...if you don't let it grow fairly naturally, you will be mowing down babys in the yard all year!