Xij, the wordplay in 37 also escaped me. But I was fairly happy that the entry was NILLS : it satisfies the definition and there are no unchecked cells. I don't have the most recent Chambers, so perhaps there is something there...
Just to confirm, the clash cells are at the intersections of 1D/20, 24A/D, 24A/25, 27/24D, 37/23, 45/25.