Ive installed a shower pan as some of u have seen pics of. I have a problem with it now. While i was hanging hardibacker, i damaged the the dry pack. I made ruts in it, holes and stuff. How can i repair it? Do i just make more of my dry pack and fill in? The holes arnt real big, or very deep. Another thing, i can run my hand across the pack, and some of it will crumble. Is this a problem?