Walker who isn't a good story-teller (7)
I believe the answer is:
rambler
'walker who isn't a good story-teller' is the definition.
'rambler' can be an answer for 'walker' (rambler is a kind of walker). I'm not sure about the rest of the definition.
'walker' is the wordplay.
I cannot quite understand how this works, but
'walker' could be 'ambler' (I've seen this before) and 'ambler' is found within the answer.
A single letter 'r' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for rambler that I've seen before include "one not getting to the point" , "Trailing climbing plant" , "Country walker" , "Presumably one goes on" , "Walker - rose" .)