Your situation is probably due to having installed and run an Evaluation version of Adagio Receivables rather than a Full but not-yet-registered copy. You can tell what is there from the Help menu and About. If you see the word 'Evaluation' next to the version, then this is the situation.

Importing and Exporting are disabled in the Evaluation versions of Adagio.

You are not misled about a Full version of Adagio being limited in functionality prior to registration; everything should be accessible. Unless Group Security has been defined to prevent access to the Import menu you should be able to use this function.

I wonder if you installed the purchased version of Adagio Receivables directly on top of a previously installed Evaluation copy. I would suggest renaming the CRWIN directory and try re-installing Receivables program, in case some leftover files from the Eval version were not removed.