Worse bit of hardware, it's a nightmare to set up (7)
'worse bit of hardware it's a nightmare to set up' is the definition.
I can't tell whether this defines the answer.
'of hardware it's a nightmare to set up' is the wordplay.
'of' indicates a hidden word.
'to set up' says the letters should be written backwards.
'reitsan' is hidden in the letters of 'hardware its a nightmare'.
'reitsan' written backwards gives 'NASTIER'.
Can you help me to learn more?
(Other definitions for nastier that I've seen before include "more aggressive", "Retsina (anag) -- not so nice", "More unpleasant or distasteful", "More horrid", "More disgusting".)