You have created 2 schemas during installation - PPM and RML - you simply need to provide these 2 users as OWNER value in exp call. PPM owner will export PPM tables and DB objects, RML will export viwes and some DB objects.
In 1 PPM Environment (e.g. Dev) you need to have 2 schemas (Base and RML). If you want to copy these 2 schemas, you need to export these 2 schemas from your source database schema and then import these 2 schemas to your destination database schema. Please note that your destination database schema should not have any objects in it yet to import the database successfully.
But if you just need to migrate specific objects from a ppm to another ppm environment just use the change/deployment management module. Just make sure it was already setup.