Not a problem on the time, I was just able to get on today anyway. Those pieces look GREAT! Just so I am understanding, they are laminate floor on top of plywood? Is that what everyone is refering to as a backer/liner board?
I use 3/4" construction grade exterior grade plywood.
Two layers glued together with TiteBond III. Clamped
overnight and then cut to final size.
Then I spread construction adhisive with a notched
trowel, 1/8 think, small anyway and lay the laminate
flooring with a board on top and weights for a couple
of hours. Trim with a router, install the batten edge.
We did a lot of these for the school and never had
a warpage problem.
One thing to watch for is defects in the edges of the
plywood, it will show up in the edges of the laminate
it you are not careful. Make a test pass around with
your router to make sure the bearing is not going
to hit one of the voids.