you can use granfix ultimate flex it says on bag its suitable for floating floors i get it for£27 trade for a 20kg bag much cheaper than others and will cover greater area
tile it all supply it they are based all over the north east also if you go on granfix website find their number give them a ring and ask about nearest stockist
Latest update...having spoken to Granfix tech support and having found a local supplier, I am going to order Ultimate Flex adhesive, with Ultimate Flex grout also. I intend to prime first with Granfix Acrylic Based Primer.
Thanks for all the advice, I will keep you posted on results (have been taking pictures)