Controlling a Device within a Rack, Beyond Macros

I have an effects rack, with all 16 macros assigned, that I include in all tracks of my template. I use the Device Selector for each track to control all of them based on where the Session Box is.

Inside of the rack I have a BeatRepeat as the last device in the chain, which is not mapped to any of the macros. For each track included in the Session Box, I would like to set a button to turn the BeatRepeat on, and an encoder to control the grid.

I know how to map the macros, as I just have to use Device Selector, set device number and set it for 16 parameters. I have no idea, however, how to point it to a specific divide within the rack, and cannot find any instructions in the user guide or community posts.

Any tips are appreciated.

Thank you,
Neil