the best way to install your flooring is to nail to a plywood sub-floor. i can not understand the love affair flooring installers here in ireland have with floating solid wood flooring. using a new product like elastion is also risky, your solid floor is also just floating on a plastic membrane over your concrete slab. i would advise you to use a professional floor installer,someone who has the knowledge and experience,able to measure moisture content in sub-floor and flooring, able to frame out plywood sub-floor and able to rack out your flooring and install it properly. pm if you need more info