I'm interested in putting an engineered wood floor into my living room that can't be floated (manufacturer recommends glue down or nailing).

Right now it has a floating laminate floor, which has some give to it that my wife likes (for her knees). In order to do the same with the engineered wood, should I try to float it or could I do a double glue down/double stick installation with an underlayment like Floormuffler or Tranquility on my concrete slab?

Thanks.

Ask the manufacturer if you can glue it to your laminate floor?

Double stick on CC? You would also have to ask the manufacturer of both underlayment and hardwood, get it in writing.
Then you would need to profile the surface and use something like Sikabond Primer SB first for moisture or else you may end up with a floating floor. lol

Of course there is that double stick underlayment out there http://www.homedepot.com/p/Elastilon-St ... /203144804

As far as I know no hardwood manufacturer will reccommend going over a laminate floor, glued or floated.