Laid new ceramic tiles on Kitchen and Utility room floor with pretty standard 12" X 12" Ceramic Floor Tiles. Some lapses of concentration by me have resulted in 5 or 6 tiles that are flexing at the edges, due to uneven floor, or poor distribution of adhesive I guess (out of total of 90 tiles though.. so not so bad really) But what to do? The flex isn't so much, absolute max of 1mm. The tiles can cope because they have been walked on, jumped on and even Washing machine and fully stocked double door Fridge Freezer rolled over! The only visible issue is of course that the grout has cracked due to the movement. Any ideas gratefully received! All I really want to do is fix it cosmetically ... stop the grout cracking.