Test screening of kiss by West gets sent up (4)
I believe the answer is:
exam
'test screening of kiss' is the definition.
'exam' can be an answer for 'test' (I've seen this in another clue). I'm not sure about the 'screening of kiss' bit.
'west gets sent up' is the wordplay.
'west' becomes 'mae' (actress Mae West).
'gets' means one lot of letters goes inside another (gets can mean captures or absorbs).
'sent' becomes 'x' (I can't justify this - if you can you should believe this answer much more).
'up' is a reversal indicator (in down clue: letters go upwards).
'mae' placed around 'x' is 'maxe'.
'maxe' back-to-front is 'EXAM'.
'by' acts as a link.
Can you help me to learn more?
(Other definitions for exam that I've seen before include "Formal knowledge test" , "Students sit it" , "One might be taken for English" , "School test (colloq.)" , "Oral maybe" .)