I’m only guessing but if you’re wearing 7mm booties it’s pretty darn cold out. If the board isn’t being glassed above a consistant 60+ degrees F it might not be curing hard enough. Plus a gloss coat on top of the hot coat is often disregaurded but I’ve never had the dents when I do it and I only do 10 or 12oz of fiberglass. I’m 195lbs with 3mm booties and our fall/winter air temps are in the 40s and 50s. I’d be real nervous about a hairdrier too, I’ve seen them make bubbles bigger than softballs when gas gets trapped inside. Did that one myself on a repair job… dremel time…