Why does the USB LicenseKey Manager show "Warning ..."? What are the technical standards required?

The technical standards requirement means that you should use the USB drive that fully complies with the USB standards and specifications. We don't have the details on the required tech specifications. They're classified by our development and also security matters. The warning basically indicates that your USB drive doesn't have the fingerprints (e.g. device IDs and characteristics) needed to make the dongle using our solution. It's still possible to make the dongle, but some security validation may be relaxed.
If you use a USB drive from well-branded, trusted companies such as SanDisk, Kingston, Lexar, Transcend,... they fully comply with the USB tech specs and standards. There should be no problem. But, OEM vendors usually don't fully comply with the firmware specs. We recommend that you should run USB LicenseKey Manager to test your USB drive first before ordering a large volume to make your USB dongles. You should also test that the protected application must be able to detect the dongle on another machine which is not used to make the dongle.