How to associate FND user to 'Other' CRM resource?

Hello,

We need to give access to customer contacts to third party portal. A user has been created for them in eBS. We can't set them up as employees in HRMS, so we have create CRM resource of category 'Other' and provided CRM access to this resource.

Now, how do we link this resource to FND user created for customer contact?

Alternately, tried to import the resource as Party resource in the import resources screen.

While doing so, the resource doesn't get imported & gives error 'APP-JTF-380060: The address id passed in is not the primary address of the party/partner '.