Now that it is daylight I went and rechecked and on the 07 30SK the center heat duct is in fact 50% covered by carpeting...not sure what year rig you have but they may have moved the location on newer year models. As far as the fridge goes, my point was that you are not suppose to operate the fridge when off-level for long periods due to the problems of air pockets forming in the system. While traveling, the movement of the rig prevents this but when parked and the slide in, my fridge is WAY off-level. Seems to me camping overnight with the slide is would be considered a long period.
I don't know about the weight on the bedroom slide. A call to Crossroads may answer that question.