Richard, thank you for taking the extra time to answer my question. I'm sure you'll agree that those who are interested in something will ask questions in order to further their understanding.
Regarding the ticked off Tictic, if someone is prepared to post a reply that is in no way helpful and is in fact rude, they must expect a 'response' back, I'm sure you'll agree that is fair. If a person cannot receive, he shouldn't give it in the first place should he? (oops,he did get a bit excited didn't he?). I have no doubt that he is to tiling what Tyson was to boxing, but we should all have manners shouldn't we? I don't see any need for an apology, but if he wants to go first..........
The kitchen wall was also newly plastered, most of the dodgy tiles had been cut with a wet cutter and were therefore damp, I wonder if that was the reason?