The schwintek slide in my funfinder ( cruiser ) trailer is exactly as Huntindog describes. These slide rooms have been described by another poster on this forum as being like "an empty shoebox, turned up on it's long edge". In my trailer this is a good analogy.
When it is extended, the open bottom edge is supported by four, 6" long white plastic ( appear to be nylon ? ) rollers which are attached to the opening of the main wall of the trailer. These rollers are mounted slightly above the opening. They are what supports the weight of the slide room.
When the room is retracted, the entire length of the lower edge is unsupported. If I accidentally step my foot on this while the room is "in", I can feel it flex under my weight.
For this reason, I avoid using the slide-room while it's in. I suppose one could slip some "shims for support" under this edge while it's retracted in order to be able to use it. The gap between the bottom of the slide-room and trailer floor is about 3/4".
There is no mention at all of it's use or not in the factory owner manual, but logic suggests that the flex of that unsupported floor is not good.
Six years now ( using this trailer 5 to 7 months per year ) of trouble free operation, so I think I will stick with what's working: avoid using it while retracted.
Just another observation from out here in the real world.
EDIT: and while I agree that a slide-room adds a potential fail point in overall trailer use, I personally would not own a trailer without a slide.
It adds so much room and a feeling of openness to the interior, it's worth the potential service risk to me.
