Description:
When starting Logic Mac the error message "This key is only licensed for the Windows platform" appears and Logic quits without giving any opportunity to enter an access code.

Explanation:
Presumably the XSKey had been running in demo mode for the Mac platform, and the demo period has expired. Once a platform demo has expired, it is only possible to enter new codes on the platform that the key is fully authorized for.

Suggestion:
Please enter the access code under Windows.