Help Getting Started

Could use a little help getting started. Please see attached screenshots.

I was trying to follow the "outdated" video at https://www.youtube.com/watch?v=rhSqDvgfrCU&list=PLa9YKhpnU_AxCLeOHuJPyM....

I created a content type Room Booking, and made it bookable with 'Flexible Bookings' for Booking Length, and 'Generally available' for Availability.

Then I created a Room Booking node, 'Mahley Auditorium'. See in screenshot there is nothing showing for Availability. Shouldn't there be a calendar widget or something there, like there is in the how-to video?

When I try to Add a Reservation, I get error 'No available units'. Not sure what 'unit' is referring to, or how I can add or make them available.

Hoping is just something simple I'm missing.

Thanks, really hoping to be able to use this module!