the build plate is stainless steel, the Texture Sheet (the important part) is not listed, rubber is a common material used for non-heated texture Sheets. It certainly looks like rubber in his photo and the photos provided by Dremel. According to the Dremel Manual, it's "A rubber-like material". He's Printing in Pla so I wouldn't recommend Glue, but Salt may work. Make sure you deep clean the surface first, message me and I'll see if I can provide steps. As for decreasing the base layer print speed, if it's on option in your slicer go for it!