The available variables covers a lot of information about the set and the song, and I tried to get the same information about the rack, more particularly the name of the current state in the rack, but could not find it.
Would it be possible to include something like RackState (and maybe RackProgram) in the list of variables? I would expect it to pick the name (and program) of the state of the rack containing the binding, and if there is no rack or no states, then just return an empty string like the other variables does when there is no obvious value.