I thought your problems were to get the old project running. Anyway I‘m entirely with dr, to switch your old project to CR requires nothing but to enable it, and set main output to „Not connected“ (otherwise it will be 6 dB hot).
As for VST Connect, you need to enable Talkback on both Main (coupled wit VST Connect TB button) and VST Connect Cue Mix in Control Room. Then Performer should hear you. Plus dr‘s suggestion to try MIX in cue channel first.
Can‘t see Performer settings, both pics show plugin config 