If so, you need SAP Universal ID. In a few months, SAP Universal ID will be the only option to login to SAP Community. Without it, you will lose your content and badges. If you have multiple accounts, use the Consolidation Tool to merge your content.
An extractor from CRM (0CRM_COMPLAINTS_I) delivers a user in the field "Last changed by". However this is the logon name of the user (i.e. JSMITH). Which table (in the source system) would contain the real user name (i.e. John Smith)?