Bloody hell, this is harder than mine, and that’s saying something. Got there eventually with some help for 17 and 20d. Interestingly I did look at doing one like this but tried to make it so all clues were thus treated - doesn’t seem to be possible to set the grid and, if this is anything to go by, wouldn’t be solvable either. That was the hardest Genius I remember for a while, and enormous fun.