Yes, and it was awarded US Patent No. 9,646,581 B2
No, just remove paper backing on glue tabs and place under strings center on sound hole and press into place.
Yes, scissor trim the top as little as possible to save material and if necessary you can lower it off center on the sound hole a slight bit .
Yes, you can lift the top area for there is no tape in the upper side of sound hole.
Sometimes yes. You can finger rub off the acid-free glue residue.
No, the reduction is only 2 sound decibels.
No, it is not designed for this.