Hello Andrew,
[Topic moved here.]
Licences are stored within the Hauptwerk USB key and they aren't computer-specific, or platform-specific, so you can use the key on any computer, and on any supported platform (including Windows 10), with no licence updates needed.
Please just make sure that you have the latest version of Hauptwerk (v4.2.1) installed, and install the latest driver for the Hauptwerk USB key. Both are available on our main downloads page:
http://www.downloadhauptwerk.com/
Also make sure that you have the latest Windows 10-compatible drivers installed for your audio/MIDI interface(s), and any other hardware that you might have, checking on their respective manufacturers' websites.