Good Morning Everyone. I recently (early summer) purchased a used camper with a soft spot at the entry door. I assumed this was leaking around the entry door and thought i would fix at a later time.(really not that soft). After using the camper a few times i was underneath the unit setting my stabilizer jack and noticed the plastic flooring "waterproofing membrane" was holding water. Not the corrugated plastic but the plastic film against the floor. I have looked and not found how the water is getting in there. I cut a slit in the liner to allow the water to exit and when not in use I leave the trailer nosed down in the front to allow for drainage. But after searching i cant find where this is coming from. It tried a few things i think i have eliminated it down to rail water. But still cant seem to find where? is there any particular area to look for? I pulled the front "alum decorative skirt" off the area but see how any water could get in there. I also re-caulked all that and still have the issue. Not sure how all this is constructed to know how the water can get in there. The is never been any water come in the inside of the unit. No signs of water on walls, ceilings, or floor(other than soft spot, which is not noticeable in the front bedroom). Any help on construction, problem areas or diagnosis method would be appreciated. Side note, this is just my second camper and third year of camping.