Problem solved. After a chat with Support, I discovered that in Install Manager, I needed to uncheck the box for "Only install files new in 2022 (i.e. upgrade from 2021 UltraPAK)". By having this box checked BIAB Install was set to NOT look for real track files from 2021. At least that's how I understood it. Thankful for Support because I wouldn't have noticed it, much less understood what it meant.