advice
 

can you add a microlight rating to your ppl as you would any other single engine aircraft or is special training needed?

wtf is a microlight rating and if you're in Leeds why would you ask this question in a forum which is supposed to cater to Australia and (sigh) New Zealand?

Training is definitely required. For starters in Australia you would need to convert your PPL across to an RA-Aus (Ultralight) licence which takes a minimum of 5 hours as detailed in section 2 of the Operations Manual. My understanding is that if you were to do this conversion whilst flying a weight shift aircraft then you would then be all licenced up and ready to go, however if you do your conversion in a 3 axis machine then of course you'll need the training required to get up to standard on weight shift.

There Pete, answering the guys question. Wasn't that hard eh?

Is Weight-shift also/alternatively administered by the HGFA?

If you join RAAus and do the weight-shift stuff you should be "grandfatherd" the 3-axis stuff on submission of a copy of your PPL.