Got the grid filled in, I think--thanks for the assist on 12ac! And I believe I've just got the parsing for 1ac, which is devilish--many little bits. The exact enumeration is spoily and I will put it after some space at the bottom.
Still absolutely nowhere on the parsing for 20ac--oh wait. Cricket?--and is 7d, 1d a cryptic definition or is there something more wordplayish going on there? I can see a definition for the 4 but I can't figure out how Antiques Roadshow comes in. Also, is 19ac a triple definition? I can't really make out the first part, if so.
Thanks to Enigmatist for the challenge!
2 minus 1, 2, 3, 3, 2