I own a registration code for Pianoteq Standard. I've just upgraded my Mac to v9. I've tried unsuccessfully to upgrade my IOS version to V9. I downloaded V9 from the App Store. It loads in Demo mode. I'm presented with a message that I can upgrade my IOS version for $29.00. I click "restore purchases". I'm presented with a screen requesting my account login information (email, password). I start filling this in but before I can finish, this screen disappears and I'm taken back to the main interface which is still in Demo mode. How do I upgrade my iPad version?

This issue may occur if there is an external keyboard attached to the iOS device. There might also be another reason so I suggest you contact our support team (if you haven't already) and they will assist you further: https://www.modartt.com/support

Good that you contacted us again so that we could clear up any confusion there.

I own a registration code for Pianoteq Standard. I've just upgraded my Mac to v9. I've tried unsuccessfully to upgrade my IOS version to V9. I downloaded V9 from the App Store. It loads in Demo mode. I'm presented with a message that I can upgrade my IOS version for $29.00. I click "restore purchases". I'm presented with a screen requesting my account login information (email, password). I start filling this in but before I can finish, this screen disappears and I'm taken back to the main interface which is still in Demo mode. How do I upgrade my iPad version?

Sorry that I don't have a solution for you, but I have a similar (not exactly the same) problem.  Note that I'd rather stay with PTQ8.

I have PTQ8 Standard installed on my 10 year old iPad Pro with about 5 pianos.  Just bought a new iPad Air (M3) and copied the Pro's contents and apps to the Air.  Although the PTQ8 app works, I only have access to the Steinway D.  I tried "Restore Purchases and ....nothing.

I contacted Modarrt via e-mail and was told to first upgrade to Version 9 (which, from your experience is problematic in itself), then to restore the purchases on PTQ8, then request a refund from Apple for Pianoteq 9!   That makes no sense to me - especially the refund part.  I've never heard of something so convoluted.

I'm not sure whether this gives you an idea to try, but at least you know that others are having similar problems to you with transitioning to PTQ on iPad.

Maybe Modarrt will do something about this and Maybe not.

Good luck!