Here are the issues I've run into:

1. Omnisphere 2.0 seems to be having some issues with freezing audio artifacts, requiring multiple freezes to get a clean take. I haven't seen this with other vsti's so not sure where this bug lies.
2. The upsample feature causes occasional crashes on freezing a vsti. Tried both fast and regular freeze along with other freeze options. So I am unable to use this feature.
3. Tails seem to not be rendering and the audio cuts off abruptly at the end of the section for a frozen track. I have to manually select a larger area or add a fake delayed note to work around this.
4. Getting some strange intermittent midi note cut offs on playback. Resetting the vsti or reloading a patch solves this.

After I upgraded I reset and rescanned all VST's multiple times. Any other tricks I should be doing?
 

The MIDI cutoff could be too low a value for the MIDI option "Prepare Using XX Millisecond Buffers" (in Preferecnes under MIDI->Playback and Recording) Mine's now set at 2500 (which I think is overkill) but whatever the default was definitely cause notes to not play or cut off early.
 

There's a Tail Duration setting in Freeze options accessed by right-clicking the Freeze button. Note that FX must be included in the freeze for the Tail function to work.

msorrels
The MIDI cutoff could be too low a value for the MIDI option "Prepare Using XX Millisecond Buffers" (in Preferecnes under MIDI->Playback and Recording) Mine's now set at 2500 (which I think is overkill) but whatever the default was definitely cause notes to not play or cut off early.
 

Thanks, So mine is currently set to around 850, which seems insanely high too, but maybe it needs to be higher. I'll try pushing it up even more and see if that clears it up.
 
 

brundlefly
There's a Tail Duration setting in Freeze options accessed by right-clicking the Freeze button. Note that FX must be included in the freeze for the Tail function to work.

Thanks
 
So no tails if I'm freezing without fx? Interesting. I turned off having the effects render with the freeze recently because I've been trying a different working process. I guess I just assumed it would still render out the tails from the vsti alone. Good to know.
 
My new working process has been to get a pretty solid base track down and freezing it, because I've been running some pretty heavy samplers (Kontakt 5, UVI workstation, Sampletank 2.5, and Omnisphere 2) I noticed my hard drive speed has been the limiting factor (only 7200 speed, no SSDs). So I get my instrument down with midi and freeze it before I go nuts with mixing/fx so I don't crash it.

Is the first core of your CPU heavily overloaded? If so this is a JP bug. Try disabling allow arm changes during playback record. If it persists after that probably time to roll back.

IMHO the next Sonar update will be far more optimized for performance than JP. Too many issues, understandable considering the rather complex functionality introduced this month...