Cubase 6 Studio also doesn’t include VariAudio. Thats the $150 upgrade from version 5. However, the full version upgrade which is $300 says it is included. Why can’t I just upgade Studio 5 to Full version and then have VariAudio?
I think the OP wants to upgrade to Cubase 5, not 6.
If that´s the case, then you can´t, because the actual Cubase version is 6, therefore 5 is no longer available officially. Simple case of “too late, too late”.
Apart from that, the upgrade price from CS 5 to C 5 is usually the same like from CS 5 to C 6, IIRC