You can use track 8 for something if you want, the track recorders work regardless of what machine and/or sequence is on the audio track. They’re kinda their own thing so you can see OT having 8 audio tracks, 8 midi tracks, and 8 recorder tracks…
You can use any of the 8 recorders and set the input source as “main” for the “Src3” setting in Recording Setup 1. “Main” as an input source will record everything you hear coming out of the OT as long as your not cueing tracks. You don’t need to enable the INAB/CD inputs as main will capture everything your hearing. The OT mixer main volume and the track level of a master track (if you use one) affect the recording volume of sampling from main, probably best to set main volume at 0 and master track level to 127.
There are several ways to initiate sampling but for recording entire performances I’d probably use a one-shot on step 1 of the recorder track. With this you would “arm” it when OT is stopped and it will trigger the recorder when you press play.