Tour manager with Carmen is upset going to rack and ruin (8)
I believe the answer is:
operator
'tour manager' is the definition.
'operator' can be an answer for 'manager' (thesaurus). I am unsure of the 'tour' bit.
'carmen is upset going to rack and ruin' is the wordplay.
I cannot quite see how this works, but
'to' is within the answer.
This may be the basis of clue (or it may be nonsense).
'with' is the link.
Can you help me to learn more?
(Other definitions for operator that I've seen before include "Person who directs or controls, machine say (8)." , "User of machine etc" , "Person who runs a machine or a business" , "Poor rate for a businessman" , "Controller, of a machine say" .)