For the stabilization issue a lot of people use x chocks, I use pyrmaid twist jacks (the camco ones) and just snug them to the frame in front and behind the wheels, for me this takes some bounce and shimmy out of the suspension. I use them because I had them for a previous trailer. If I didn't I would have tried the x chocks, there are a lot of great reviews of them on here but I just have never tried them.
I cant help on the AC, sorry. I know there was a few threads from a couple days ago about A/C problems so it seems you are not alone and I am not sure if your problems relate to theirs. I'd trust the dealer to take a look and see, if anything you should still be under warranty so now worries there.
2015 Forest River EVO 2850
2012 Dodge Ram 2500 6.7 Cummins
Yamaha 2k x 2 with parallel cable
EMS 30 PI portable w/ Edison plug
Nights Camped (2016-13) (2015-13)