I am working with MDM and loaded catalogue into MDM import manager. I did Mapping fields/Values and table mapping in Import status tab shows "Filed mapped 30 of 30". But the Import button (the exclamation point) is disabled in Import manager toolbar to import this to data manager.
Did you performed matching step of data import in import manager.. I mean after you map fileds and values, you have to define field/s based on which import manager will compare source records with the records existing in MDM repository. Once you define fields for matching then define default import action like create if no match is found in the repository, update null fields only if match is found etc.