Water Stops Missin, Drainage Issues

Hi there everyone i was hoping to get some details and some clarification on some potential defects that may have occurred our recent bathroom renovation.

1. There seems to be no water stop angle at the entrance of the bathroom or in the shower. Are aluminium water stop angles a minimum requirement at the shower and door way and the lack off considered a defect?

2. During the renovation process and before plumbing was done I also noted that an existing drain (charged by the shower) needs to be moved due to the floor mounted bathtub dissecting the centre of the drain. (All other drainage was moved. The edge of the bathtub now sites directly over the drain limiting access. Would this be considered a defect?

3. A new cavity wall was also installed to hide the plumbing and has resulted in a 20mm variance with the bottom and top of the new wall where the shower screen is to be installed. Would this be considered a defect?

I have raised these issues with the builder and he has stated that all is correct and there are no issues.

And for some additional back story we had issues with the fall of the floor only being 2mm in the shower area which he has finally come around to rectifying which seems like a quick fix. Would anyone have any recommendations for what would be required to fix the fall of the floor as well.

Thank you.