Just purchased allure flooring for my basement. The cement floor is not level and I am wondering if anyone who has had experience laying this type of flooring can respond to the need for a level floor and any problems faced with laying it upon a plastic moisture barrier.
Mr. Jay here with The Home Depot. Hopefully I can help with some of your concerns on this install.
As far as having the floor level, the tolerance of the product is about 3/16th of an inch over a 10' span. It is a relatively forgiving product, but I would address any issues over that amount.
For the vapor barrier, the only problem that I would see is that the sub wouldn't really be able to breath through the allure, and may mold on the barrier over time. So while you theoretically could lay right over it, I would look into getting a water-proofer of some kind down on the floor first if you really feel that it's going to be an issue. Have you had problems with it before, or tested it recently for moisture?
Hopefully that helps you out and the install goes smoothly :D let me know if you have further questions~