Hopefully this isn't classed as thread necromancy..
I have a similar situation thanks to a bad tiling job, my shower really started to leak water and I noticed all the grout was cracked. The tiles are all raised on thick dabs in the centre of the tile, so the grout is essentially suspended between the tiles with a void behind. The shower is on a wooden floor, so the movement has cracked it, letting the water into the voids. Removing the grout, one of the tiles came off. The problem is I only have this one tile, (about 45cm by 30cm) so I need to re-use it, and the company has gone bust, so no chance of any more.
Will try the "soaking in boiling water idea", but I'll warm tile with progressively warmer water first as I really don't want it to crack... but does anyone have any other ideas? I don't have an angle grinder (and would be worried about smashing the tile). Would a sander work?
Now.. which forum do I look in for answers on how to repair the plaster behind the tile? The surface seems to be shedding like sand. Not the best for attaching tiles to!
Thanks for any answers folks!