On start and close of conference, took on Rome, returning yet again (4,4)
I believe the answer is:
once more
'again' is the definition.
(synonyms)
'on start and close of conference took on rome returning' is the wordplay.
'start' becomes 'c' (I can't explain this - if you can you should believe this answer much more).
'and' is a charade indicator (letters next to each other).
'close of' says to take the final letters (the letter which ends or closes the word).
'took on' is a charade indicator (letters next to each other).
'returning' says the letters should be written in reverse.
The final letter of 'conference' is 'e'.
'e'+'rome'='erome'
'erome' written backwards gives 'emore'.
'on'+'c'+'emore'='ONCE MORE'
'yet' acts as a link.
This may not be correct. It may belong to another bit of the clue.
Can you help me to learn more?
(Another definition for once more that I've seen is " Again".)