Presumably it's a UK NPPL with Microlight aircraft rating which you're training for? Or are you removing restrictions from an existing PPL(M)?
With either licence, your next step would probably be to use the cross-credits to which you will be entitled in order to obtain a NPPL with SEP aircraft rating. That will mean that you'll be able to fly with passengers in simple SEP aircraft in day VMC in the UK. Later, you can then upgrade that to JAR-FCL PPL(A) with SEP Class Rating. See
www.nppl.uk.com and look under 'Licence Allowances'.
The maximum credit you would receive for 3-axis microlight hours when applying directly for any JAR-FCL licence? 10% of the total
up to a maximum of 10 hours. So, if you go via the microlight to NPPL SEP route, you will have a reasonably cheap route to obtaining a licence which will let you 'build hours'
in the UK only; if you later upgrade to a JAR-FCL PPL(A) then you will be able to start a Modular CPL course when you have the appropriate hours....then the IR.
But whichever way, you'll still need to take all the JAR-FCL CPL or ATPL exams as the PPL ones are totally different.
The CAA's 'LASORS' is a publication which spells out all the various requirements, plus it contains valuable safety information - the 2003 version only cost £10 and the 2004 version has just gone to press. I recommend it to any one embarking on the long and stony path to the ATPL. Good luck!!