Hello biogon,
Just to confirm and add to Grant's reply (thanks, Grant):
All Milan Digital Audio sample sets are available in v5+ format, so that they can be used in v5+ (including v6) -- you wouldn't need to buy any of them again. Also Hauptwerk v5/v6 are still supported on Windows 7 (although note that Microsoft no longer support Windows 7 or provide any new security updates for it, so using Windows 7 on any computer connected to the Internet could pose a security risk).
For upgrading to Hauptwerk v5+, you'd need to buy the v4->v6 upgrade itself, and optionally (but recommended) buy an iLok3 dongle from your preferred musical equipment shop, then follow the instuctions in the '
Upgrading or re-installing Hauptwerk' section in the main Hauptwerk user guide (pages 25-29 in the current v6.0.1 version:
https://www.hauptwerk.com/documentation/ ). (I understand that migrating the sample set licences to v5+ now involves an additional cost of $30.) The proces is a bit more involved than most Hauptwerk upgrades, due to the change of licensing system between v4 and v5+, but it isn't difficult, and there are a lot of major improvements in v5 and v6, so hopefully you'll agree that it's worth the extra bit of effort, and we're here to help if you were to you get stuck.
However, of course v4 won't stop working, so if you prefer to stick with your existing v4 system then that's fine too.
Best regards, Martin.
Hauptwerk software designer/developer, Milan Digital Audio.