Hi all, bit late to the table! I enjoyed this a lot, overall - some excellent clues. But agree that there were a few questionable ones, especially 20d which was a messy unsatisfactory clue. I also (like some others) wondered why 'Bit of' was at the start of 18d.
Only one I still can't parse is 21a (despite hints on here) and am wondering if my answer is correct (I have a country in Africa). I can parse the last 3 letters. But if the film is ET (is it?) then I'm left with HEO and can't make a 'leaderless state' out of that!