We have a 2006 Signature had a similar leak with heavy rain thought it was the door awning but it turned out to be the front mount on the large roof awning. Oregon Motor Coach scrapped and resealed the area around the mount with self leveling sealer and at the same time put a good bead on the door awning top seam for future protection. Inspection of all other mounts on both roof awnings was fine. They created a water pool in the front right corner and ran a hose up their for 20 minutes to test it. Problem solved.
