I am applying the gray and notice that is stays pliable in the heat. Is this normal?
Yes, that is the characteristics of the material. Product should be below grade and not on surface, therefore it should not track on an extremely hot day. It will soften on very hot days, and will leave an imprint, but it should not track. I would recommend lancing/ heating the crack filler just so it will receive a dusting of sand. This will create a barrier, and it will significantly cut down the surface tack.