Just a little bit from lasors:
Training for the Night Qualification must be in accordance
with JAR-FCL 1. Training may be undertaken in a non-
JAA state provided that the organisation is fully approved
in accordance with JAR-FCL 1 by the UK Civil Aviation
Authority.
So the answer to your first question - Yes
and the second - you might as well sent your forms in when you send off for your CPL because they will do it all at once and it will save you 84 quid. Just make sure your instructor has signed it to say night qual completed in your logbook if you would like to fly at night PIC.
Hope that helps