The App Store states this automatically because we just left the minimum required iOS version field to iOS 8, as it was before.
We didn’t expect that Music Studio would exhibit this bug on iOS, since there were no changes done to the graphics engine.
If we had known, we would have increased the minimum version accordingly.
We’re very sorry, but updating iOS seems to be the only solution to this issue.
This is a limitation of the App Store, we can’t do anything about it, as much as we would like to offer you a previous version.