If your for-sale MP3 files did not migrate, it means that your MP3 file(s) do not currently have a rights category assigned (i.e. we don't know if your MP3 is "Public Domain" or "Original").
You should have received an email asking you to identify the rights category for any affected assets so that we can migrate them successfully. Please check your spam/junk folder in case the email was caught/intercepted.
If you did not receive an email with those instructions, please reach out to us at firstname.lastname@example.org with the subject "My missing MP3 rights categories" and provide the rights information for each title and we will be glad to get those updated and migrated to your ArrangeMe account.
(NOTE: This pertains to for-sale MP3 files only, not demo/preview MP3 audio which is a separate element and may be uploaded to ArrangeMe during the song registration process.)