Hiya Jim Bo.
It sounds to me like the tiles are at fault.
Bear in mind the tiles are from B&Q and you never hear anyone on here saying what a great tile they've just fixed from there. They are notorious for mixing batches of tiles, so you get different sizes, shades and glaze finishes. They really don't care what they sell, so problems like this are very common.
Did the tiler know that the customer was having 60x60 porcelain that needed the wax removing when he quoted for the job??? This could take him hours/days to remove, you can do more damage removing the transit wax than the transit would have produced.
If it's been laid i doubt B&Q will be helpful as they were deemed fit for purpose when fitted, in which case it's then the tilers fault for not checking.
Personally i refuse to fix any B&Q tiles for precisely this kind of problem.
Some photos will be helpful as it's not easy to visualise what is the problem.
