>> Although I did have reservations after upgrading from 11 to 12 and being used as a tester for the the upgrade (it was full of bugs).
Sorry, I do not recall you as an active beta tester nor I can see that your name or email is registered as a beta tester?
I could not find any feedback from you for the beta versions since the development of Helium 12 started, nor any accounts connected to your name/email.
All I could find was a support ticket from you related to Helium 12 registered on the 4th of October 2016 which was not a "bug".
If you have any further details related to the above, please share them with us over http://support.imploded.com (recommended if personal details are involved)
>> On reading the upgrade notes I was shocked to find that this upgrade "fixed various bugs etc present in 12".
Are you referring to the official release notes for Helium 13? (https://implodedsoftware.wordpress.com/2017/12/07/helium-13-is-now-officially-released/)
It mentions nothing about "Fixed various bugs etc present in 12", Helium 13 comes with many new features which was not included in version 12.
it also comes with performance fixes (optimizations) and of course some fixes, which naturally gets implemented when components and so are updated.
A lot of "fixes" as well as new features was implemented during the lifecycle of version 12 (please see additional details from our announcements).
After about ~16 months after version 12 was released we released Helium 13 with new features and other changes. This is how our normal product lifecycles works.
My current version of Helium is 12.4 so when I was informed that there was an upgrade for Helium and asked if I wanted to upgrade I of course said yes. Although I did have reservations after upgrading from 11 to 12 and being used as a tester for the the upgrade (it was full of bugs). Anyway I installed the upgrade to 13 and was then being asked to pay for it. On reading the upgrade notes I was shocked to find that this upgrade "fixed various bugs etc present in 12". The normal course of events in the software life cycle is for upgrades to rise in increments fixing bugs in the current version for free. Once these have been ironed out and new facilities have been added then a completely new version is created and the user charged for the upgrade. I will not be paying Helium for bug fixes to 12 that should be free. In fact I may well look for another Music manager as I have no wish to continue paying for the privilege of being a beta tester.