The Schwintek slide will close correctly top to bottom with the side seal the same, IF the slide room is OK. From your description, there is a problem with the way the room is closed. The bad news is, Schwintek slide rooms like you have in the StarCraft are susceptible to leaks coming from the top even when the top and upper sides are TIGHT. Most Trailers have a 2 inch rain/drip gutter(not the roof line but a few inches above the slide room itself) to keep the flow of rainwater running off the upper roof down onto the top of the closed slide roof and that water WILL find a way to get in. Look at this Jayco in the link to see what this drip rail looks like. With a Schwintek slide room IF you have space to add a slide topper I would ALWAYS have a slide topper to prevent excess rain water from getting to the top edge. The TORQUE of a Schwintek is at the top where the motors are, BUT if the bottom pooches out that 3/4 inch, there is nothing to do with using the motors to realign to room. The ONLY solution is to either pull both sidewall racks and realign the tracks and gears(upper and lower) to get straight. But, I doubt this is your problem. IF the room extends correctly and seals all the way around, then the room is correct. If the bottom pooches OUT 3/4 inch when retracted, then when it is extended, the TOP should have a gap of 3/4 inch which you probably do not have. If you did it would leak when extended. Until you get it fixed, I would store the RV with slide room extended. Doug
https://www.rvtrader.com/listing/2020-Jayco-Jay-Flight-SLX-265RLS-5010141791