24a Theatre's right to tackle modern copy (7) r-p-i-t. Pretty sure that the answer is reprint, rep = theatre r and t = right, but what has in got to do with modern? Surely it means popular rather than up to date?
Guys - think you're missing something here. 18d (7) must be swarthy (what's odd about radical youth leader? He's not pale). This being the case, the original answer in question ends with a t, which makes reprint correct rather than replica.