We travel many uneven roads and developed a system to secure drawers and doors. Nylon rope strips.
The closet doors we tie together, latch to latch. The drawers beneath the cabinet top we tie off the bottom drawer and run the rope through the upper handles and tie it off at the book "retaining rods". The two doors below our sink we tie together. The room divider that you pull across the hallway for privacy... I put a sheet rock screw into the frame and tied it up to the horizontal bracket. The guides that run across the rod when you use the privacy rod... I do not know what you would really call the part... holds it tight and it does not cause a problem.
The pantry shelves have never been a problem. The spring held upper cabinets have never been a problem. It seems that anything that uses those cheap plastic door/drawer latches ARE problems. Eventually I will replace those with something that will do a better job, but will still "strap" them all with rope while traveling.
If you look at how your shower door is hung, it is probably not square. Ours is off quit a bit from the factory, but does not affect the door latch. The handle used in the 2006 looks like something that belongs on a Mack truck hood opener, not in an AS. (Newer models use a flush latch without the big handles.) I would put a small sheet rock screw into the outside frame and tie the handle down with a shoe lace or short piece of tough cord. Although all of these suggestions might not seem to be proper solutions, I have not experienced these problems for thousands of back country travel again. Works for me, cheap to do and effective.
These are for the 23 foot AS, so your hardware might be different, the idea works if you take the time to adapt a way to tie everything down.