New Custom Reports for QMMAD using different matching attribute (extension4)

I'm surprised that this question hasn't come up many times.

We are using extensionattribute4 as our matching attribute for contacts/groups/users which is totally supported within QMMAD. However we find ourselves when using enterprise reporter unable modify the default report within ER to use this different attribute as it seems that the report is hardcoded to use extensionattribute15. 

What im looking for is either 3xcustom reports using extensionattribute4 for groups/users/contacts


The default reports modified in a way that the matching attribute can be updated.