Going OK so far, thanks for all the help!
Just got a few things I want to check before going any further.
When doing the pieces above the window, not the return, the pieces on the actual wall above the window. What is the best way to hold these in place while the adhesive sets? The adhesive I'm using seems pretty good, but the weight of the tiles gradually drags them down. I used gaffer tape on the top left corner of the window, but the next peices have nothing firm for the tape to grab onto.
The other thing that I had a feeling wouldn't go well is the bath side panel. The bath is quite a deep one and even with a low profile trap touching the floor, there's a large gap at the bottom of the panel. First thought would have been to cut the floorboards and put the trap under the floor and recut the waste pipe hole and then lower the bath, but there's a joist in the way, so that's a non starter. I've been looking around for a kit or something to maybe make my own. Can anyone recommend anything that I can then tile onto?
I also have a few, maybe 10 mosaic pieces that are loose. I have pulled a few of them out and was just going to stick them back on when I make the next batch of adhesive. Is that the way forward or do I need to use something else to stick them on?
Thanks again