I have the 2008 Starcraft RT14 OFF-ROAD POPUP and when the top is up it is very stable in the end to end sides but the front to back will move a good six inches or so. I can stand inside the door way and push out above the entrance door and it moves big time in that direction.
This is so bad that if I have things setup on portable cabinets type drawers etc where I sit my HDTV or microwave on the top shelf when the wind comes up all of a sudden it has knocked them off the shelf. I was lucky that nothing got damaged.
My fix was to add some one inch eyelets in the four corners of the top section that go all the way thru the top wall to the inside of the trailer. This is up behind the VALANCE curtains I have all around the trailer so not in view. I used large washers on both out side and inside tightened down with the nut. This allows me to run a set of those 1/2-wide ratchet type 15-foot long web straps from the roof area down to the ground where I use one of those 3-inch screw-in earth 18-inch long augers into the ground. These do not disturb the earth and when you remove them it only leaves a small disturbed area in the soil.
This also gives more high wind protection as well...
I use my off road trailer setup alot for emergency comms back off the trails and this really makes for a real stable top setup. Easy to setup and take down...
Might work for you to to get rid of the leaning to one side...
Roy Ken