Darby, You are correct in diagnosing as to how water is getting into the compartment. You will need to start at the top of the slide out room seal and make sure that the top seal swipe is over the two side seal swipes. Fill the two side seal and top seal corners with a good silicone, preferably black urethane. The two side seals need to over lap the bottom seal and again seal the corners. Let all this cure before using the slide out for a day. If you will draw in the slide out a couple inches and on the inside look at the top of the room, you will see that the sealing is on the small "D" seal and that affixed to the wall is a double bulb with a sweep seal that does not look like it is going to do anything. You are correct in assuming this does not seal well and this is another fix that is needed. Now bring the room in even farther so that you can take a closed cell foam rubber block about 1 1/2" x the length of the room and place (glue), with double sided tape, this block seal under the "D" seal on the inside room flange so as to creat a seal for the block seal to meet the double bulb seal. The double bulb seal is on the main wall and when the room is out the inside flange of room seals to the inside bulb and when the room is in, the outside flange seals on the outside bulb. The sweep part of the bulb seal just acts like a windshield wipe to swipe of any clinging water to prevent it from getting the carpet so wet. If you contact Gulf Stream with the unit number, they may send you the block foam seal and double stick tape at no charge and if you feel confident enough you could do it yourself. If not you could print and explain this process to a repair facility and get the issue fixed. Good luck and leet me know how you do.