There are three that I cannot parse.......
14D: Able to remember plunderer endlessly pinching wine (9)
The answer is "retentive" = remember (def)
Why, please?
18D: Sort of cinema way up by this writer's home (5-2)
"Drive - in" = sort of cinema (def)
way up - rd (reversed)
?????
20D: School head set up current ruddy course programmes! (7)
Syllabi = course programmes (def)
S - school head
i - current
Cannot do the rest of the parsing
Explanations appreciated, please!