OK, I got started on this project the evening before I was going to go on a tour, and it did not go too well. I started trying to remove the glue from a 4 year old pair of BD Ascension skins that were really wasted with lots of debris, including hundreds of Lady bugs that got stuck on there. First I nailed the skins down on a scrap piece of OSB with the hair side up, and scrubbed them like crazy with simple green, rinsed well, and hung up to dry while I went for a bike ride. Next step was to nail them down to the OSB with the glue side up, and start with the brown paper bag system of glue removal....6 bags later, and the glue was starting to look real clean, so I tried to stick one on my ski, and it worked like new! So I just repeated the process to the other skin, and they work awesome!!! I never tried to put the new glue on the skins, I just revived the existing glue. I will save the glue sheets until next time and try to install them then.
By the way, the trick to removing the glue seems to be to work slowly by heating the paper with the iron, and slowly start lifting the bag an inch or two at a time, while moving the iron slowly ahead on the paper that is being lifted, rather than heating a larger area, then trying to lift it off. The paper will just stick to the skin glue. The iron needs to be very hot to work at all. You will need about 25 brown paper bags to do a pair of skins and a lot of patience! I just cut the bottoms out of the bags, and cut them down the middle into two sheets, which is enough to cover one skin. The glue only comes off in very little amounts at each heating. The good news is that you might be able to just revive your glue the way I did, without paying for the renew sheets.