Since I have uninstalled EZ Drummer 2, I continue to have two weird issues: one is that some synths won't freeze correctly, but here is the major problem today:
 
One of the synths (RealGuitar) will play just fine but it will not export.  There are two instances of RealGuitar and several other soft synths.  All the soft synths, including the first instance of RealGuitar, export just fine.  The second instance of RealGuitar does not export.
• I play the track and I can hear everything.
• I export it in real time to include Live Input, and the second instance does not show up in the wav.  It does not matter whether I do an audible bounce or not.
• The second instance is selected and going to the same guitar bus as the first instance.
• I even deleted the RealGuitar instance, created a new one and copied the MIDI and settings over and got the same problem.
 
I have triple checked busses, outputs, routing, levels, selection, and everything I can think of.  Thoughts?

More strange info:
 
•  If I solo just the two RealGuitar tracks and their MIDI tracks, they export fine.
•  When I export the entire mix, one of the RealGuitar tracks barely meters.
•  When I play the song (not export it), everything meters normally.
 
So, when I export audio, one of the RealGuitar track's volume is strangely turned down even though the fader is in the correct position.  Again, this all began with the &*^%ing EZ Drummer 2 issue.
 
Ideas most urgently sought.  Thanks.

konradh . . . I have always found using multiple VST instances of RealGuitar in a Sonar project to be a bit of a bugfest
 . . . never been able to pin it down, but I also have experienced "exporting to audio" issues with RealGuitar going missing. If I freeze those tracks before export, the problem goes away.
I've often wondered if it's related to having projects which previously had RealGuitar 2, and then I upgraded to RealGuitar 3, but not sure if this is your situation ?
Sometimes, sections that use the higher midi notes (up and down strums) are problematical on audio export.

Interesting information.  I never had problems with RealGuitar before EZ Drummer 2, but maybe I was lucky.
 
Freezing would be fine, EXCEPT freezing was one of the things that broke in the EZ D 2 upgrade.  (Since I have uninstalled EZ D 2, I will see if other projects are OK.  The one in question is definitely corrupted.)
 
My workaround:  I can export the guitar as a wav even though it won't export with the rest of the track.  I will export it and then drag the wav back into Sonar for the mix.  Kind of a pain, but I need to get this song finished.
 
Thanks.