Register put up in hall, or nearby (5)
I believe the answer is:
enrol
'register' is the definition.
(enrolling is a kind of registering)
'up in hall or nearby' is the wordplay.
'up' says the letters should be written backwards (in down clue: letters go upwards).
'in' indicates the answer is hidden within the clue.
'lorne' can be found hidden inside 'hall or nearby'.
'lorne' in reverse letter order is 'ENROL'.
'put' acts as a link.
(Other definitions for enrol that I've seen before include "Enter" , "Loner inclined to join in" , "Join as member" , "Enlist" , "Loner (anag.)" .)