New build with a floating floor advice needed should I tile the floors or will they crack?

Your concrete needs the laitance removing first, you can then screed the floor to SR1 specifications it is then advisable to use a decoupling membrane such as Schluter Ditra matting before installing tile with a flexible adhesive and grout. I would also agree that a LVT would be the preferred option especially due to cost and I would advise against both manufacturers (Amtico and Moduleo) their quality has been a little suspect of late, Polyflor Expona, mFlor, Quickstep Livyn or Project Floors all offer quality LVT and at a much more reasonable price point than Amtico especially. If you choose to go with LVT you will require similar prep work as stated above with the exception of also requiring a liquid DPM, your flooring installer MUST perform a Rh% test to identify the moisture content of the slab before doing anything or advising any products or services.