I have not really had much trouble. Most of my trapping has been with medium frames. One bait comb and 7 foundationless. That makes it important to keep the side to side on the trap level to prevent cross-comb. Always take a level with you when you hang your traps if you are using foundationless frames. If you don't take the care to level, you may end up doing a cut-out from your trap - I speak from experience.
I made up a bunch of these short hangers, they are easy to carry and hang. The vertical piece came out of a lowes dumpster - it is from the runners the metal banding goes on when they get a pallet of lumber in. They will generally have no problem letting you take that stuff for free. I put a dado wide enough for my ratchet strap to go through. The cleat on the hanger is 3/4" plywood - I usually paint the exposed grain with several coats of titebond III wood glue, letting it dry between coats. Under the cleat, is a piece of scrap to support the bottom of the swarm trap.
I have a mix of traps, some with the hole in the end of the box, some with the hole in the side of the box. I hang mine standing on the bed of my truck at a height out of reach of kids, and comfortable to take down when full of bees, and possibly honey if I get side-tracked. The cleat on the box is just inverted from the one on the hanger.
For leveling the vertical, I just add a stick between the hanger and the tree - just wedge it in until I get my box leveled - it's rare I need to shim out the top of the hanger - just look for straight trees before you hang. I will often put a second strap around the trap and the tree to hold everything in place. I trap in bear country and have lost a couple traps to bear.
PAHunter62