Refrained from releasing a book that's marked (7)
I believe the answer is:
stained
'marked' is the definition.
(I've seen this before)
'refrained from releasing a book' is the wordplay.
I cannot quite see how this works, but
'from' could be 'in' (I've seen this in other clues) and 'in' is found within the answer.
'a' is present in the answer.
The remaining letters 'sted' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'that's' is the link.
(Other definitions for stained that I've seen before include "Like many church windows" , "Church feature - side sold was wanting (anag)" , "Marked, discoloured" , "___ glass" , "Soiled" .)