Hi I will answer the questions as best as I can.

1. The foam actually will stick to the glass really well, the only thing I would worry about is seeing the white foam on the sides.
2. Not sure.
3. I know that it is possible but I have never tryed it myself.
4-5. I would maybe do it in layers or it doesn't dry as fast, also I poked holes in the foam with toothpicks and misted the foam.

I hope this helps!