AFAIK mis-alignment is pretty obvious but am no expert. Was a post about comparing the graphic tape stripes on the side with the slide to see if the stripes still line up ISTR.
The question about awnings is clever. If they resist rolling out/in part way along?
On ours I now have to lube the entry of the square tubes that the slide's arms go into. The weight of the slide makes them rub on the square tube going in and out where I suppose they should have a space all around? Anyway, it wasn't rusty teeth and all that, it was where the arms rub on the entry of the square tubes. Lots of spray lube in there and it works for a while, then I have to get under there and spray it again.