There in Scotland, nothing very fixed, as British capital intervenes (6)
I believe the answer is:
overby
'there in scotland' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'nothing very fixed as british capital intervenes' is the wordplay.
'nothing' becomes 'o' (looks like zero - 0).
'fixed as british capital' becomes 'b' (I can't justify this - if you can you should give a lot more credence to this answer).
'intervenes' means one lot of letters goes inside another.
'very' going around 'b' is 'verby'.
'o'+'verby'='OVERBY'
Can you help me to learn more?
(Another definition for overby that I've seen is " little bit off".)