If you take a look at the picture below you can see my tiles are a mess. We are in central Texas and the tiles were put in the day before the big snow storm and the plaster was done a few days after the big thaw. Tiles shifted when they plastered as they did not adhere well. To me it appears that the plaster came out between the tiles. PB says they should be plaster between tiles and plaster guy says grout. Which is right? Plaster guy says tiles will look more uniform and blend if they use a gray grout. If they do plaster, each tile will look individual and won't be a clean line. I have read conflicting articles. They have to do a full drain and fix the tiles and some other plaster issues, what really should be done?