I missed this one when it was posted. For a few years, the pad composition wasn't right and over time it turned to gum. Sometimes just one color of the foam chips, like say, the black ones decomposed and the rest were ok.
To make it slightly less messy to clean up, I only removed one strip of pad at a time. That way I could kneel on the existing one to stay clean, while scraping and sweeping the residue from the one I removed. I used either a dull razor scraper or a 6 inch drywall spreader in tandem with a hand broom to sweep the mess into a pile so it wouldn't re-stick. I suppose mineral spirits would remove it pretty easy. If a person used lot of alcohol to do this, it might be a way to blow up the house if an appliance kicked on or has a pilot light.
You'd still need to be careful with mineral spirits and keep windows open.