B
Bill
Some advice from me then...... nothing said on this forum will settle anything, legally.This was my first post, I haven't raised shading as an issue and my comment in bold is hardly one from someone who is trying to wriggle out of paying the tiler. Perhaps reading all posts before making a judgement about me would help. Although there are quite a few now!
The only thing the advice on here will do is either appease you or not.
Taking this forward, you need to get a Fired Earth rep in, the tiler back and possibly a sealing manufacturer expert in (by in I mean in your bathroom) so that this can be done scientifically to settle it. Distance finger pointing is like watching Midsomer Murders and guessing 'whodunnit' during the opening credits.