My understanding is that the multi course is a SIX hour course - plus a flight test.
I also believe that to convert your ICAO "multi rating" - you would need a total P1 time of 70 hours, pass a multi engine written examination paper and do a multi engine test flight wioth a JAA examiner.
I said "total P1" - not "multi P1".
Nutshell: The six hours training will do, do a written exam and a flight test to convert (and write a cheque to the CAA).