"looking deaper it says that if you have flown 100 hours, and also done a cross country flight of over 100nm to two diferent airfields in the last 3 months in an ICAO contracting state then the nav test can be wavered."
Wherever did you get that idea?
NPPL/XC REV06.6 gives no such dispensation for NPPL(Microlight) holders wishing to add a SSEA Class Rating. However, for holders of non-UK ICAO licences (e.g. someone who holds a current and valid FAA PPL), the allowance towards the NPPL (SSEA) is:
2.3 Non-UK licences
The holder of any licence issued by an ICAO Contracting State who wishes to obtain a NPPL (SEP) should contact the NPPL (SEP) assistance advisers for advice on the specific requirements for licence conversion.
These requirements will be determined by the holder’s current experience and will be assessed individually.
The applicant must also have passed the JAR-FCL PPL (A) Air Law and Operational Procedures and Human Performance and Limitation examinations prior to taking the NPPL (SEP) NST and GST. However, holders of such licences which are current and valid in all respects who have flown a minimum of 100 hours as pilot of aeroplanes shall be credited the NPPL NST if they have also flown a minimum of 5 hours P1C cross-country flight time in UK airspace in the 12 months prior to the date of licence application.
Incidentally, I trust that all the SSEA training was conducted from a licensed aerodrome?