The 3ed pic down shows the damage the previous owner caused by trying to make the lower bottom of the slide flange "D" seal make better contac. The area of Slide flanges BELOW the actual main floor line is NOT critical to get the "D" seal to touch or compress. That area on the side lower metal roll wrap is NOT an area that needs to be weathertight. In your 3rd pic, that gap where the metal bends out, will allow water to flow inside and run the slide wood floor. Clean and just seal the gaps with DAP ADHESIVE /SEALANT from Lowes or Home Depot. Doug
