This is more of a report for support and anyone suffering from the same issue than seeking a resolution on my end. I’ve got a workaround for the time being but here’s what I’ve found.
If you’re coming from a project on a previous version of Nuendo or Cubase - in my case from Nuendo 7 to Cubase Pro 10 - and have done a lot of direct offline processing in your session, opening the session in Cubase Pro 10 is immaculate except for one major flaw.
Cubase Pro 10 maintains the history of direct offline processing that you’ve done, plays back the files correctly, but will now be unable to be edit these files using direct offline processing. For example, I listened to a clip that I had sent through some stereo-imaging, EQ, and resonance reduction in Nuendo 7. All of the plug-ins showed up in Cubase Pro 10 in the direct offline processing history, all with the correct settings, and the audible result of that processing was still accurate to the original session in Nuendo. However, when I dropped another EQ on there in Cubase Pro 10 and attempted to preview, apply changes in the plugin, auto-apply, discard changes, etc. the direct offline processing window could not even play the clip back to preview it. In fact, the clip nulled itself. I’ve tested this both in creating a new version, undo-ing to the point of opening the session, and the result is always the same - a blank audio region in place of the working audio region that was there in the first place.
For my purposes, I’m exporting a multi-channel supported AAF to maintain the integrity of all the processing I’ve done so far as printed audio. I’ll lose my processing history, but the clips will sound the same as they do now and I’ll be able to edit them in the new session. Using the offline processing window and adding/changing effects works flawlessly outside of that so thankfully the session isn’t totally ruined.
Hope this is helpful to support and anyone else transferring from old software.