I do own Komplete 12 UCE which doesn't contain any version of Ozone not even the standard one. Would it still work If I crossgrade from that version or do I have to own any Ozone version on my NI account?
A crossgrade means that you then would own ozone advanced, the base product you need is the one you own and you don't need ozone in your native account. You can check it for yourself to be absolutely sure on the shop website, you have to be logged in and then you'll see if you can buy the ozone advanced crossgrade.
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