Contact the Dutch Authorities.
Microlights are outside JAR-FCL. Thus everytime JAR-FCL refers to aeroplanes, this means aeroplanes but not microlights.
Thus your national authority may take the view that the authorisation provided by your SEP rating applies ..........to single engine aeroplanes but not microlight aeroplanes.
The UK says microlights are not single engine aeroplanes if you are claiming the experience but they are if you are using a SEP rating to fly one.
Of course, the very important words in JAR-FCL regarding microlights is that they are "defined nationally". Thus we have the UK 450Kg upper limit for microlights but elsewhere in Europe, the limit could be higher. This means that if you can get your hands on a 460Kg aircraft registered in a country that allows this to be a microlight, you can indeed fly a microlight and have the hours count towards the requirements in the UK for CPL license issue.
Come on EASA and we can sort this mess out.
Regards,
DFC