Guide our group, leading that woman (5)
I believe the answer is:
Here is my best explanation:
'guide' is the definition.
(ushering is a kind of guiding)
'our group leading that woman' is the subsidiary indication.
'our group' becomes 'us'.
'leading' means one lot of letters go next to another.
'that woman' becomes 'her' (I've seen this before**).
(Other definitions for usher that I've seen before include "Person employed to put you in your place", "Court or parliamentary official", "Doorkeeper, escort", "whose house collapsed?", "Show in - escort", "Person whose job is to conduct others", "One showing to place", "may be match participant", "Helper at wedding" and "Escort (to a seat)".)