[JRTJH]

I'd suggest that you think about the way the trailer was "engineered"... It is designed to be supported without twisting when on the wheel/axle assemblies. It really sounds like you've somehow got one corner or one side blocked up higher than the rest and as a result, you're twisting the frame.

Start over. First, pull in the slides, then jack up the front, take the blocks out, lower the front, take the rear blocks out and level the RV by putting pads under the wheels to level it side to side. Then use the tongue jack only to level it front to back. In that condition, the doors and slides should work properly and not bind or sag. Once you know that it is capable of being leveled when supported on the axle/wheel assemblies, then start putting blocks under it while maintaining that same degree of level. Work from the axles toward the front and toward the rear evenly. Don't go to the front or rear and try to level it and work to the center, if you do, you'll not maintain the proper "bow" in the frame rails.

RV frames are built slightly bowed, that allows the front and rear to be "level when all the weight is on the axles. When you block it, you have to keep that "bow" in perspective and not block both ends at level. Doing that will essentially "push them up" causing the center to be "lower than intended" and can cause the doors to bind.

Good Luck, but I think you need to start over with the leveling process....