Status update! First, the bad news:
There is a lack of complete documentation for Johto tracks so I'm hunting a few down, which makes things take longer.
Additionally, looping is not possible due to client side technical shortfalls. While I can still loop the tracks manually as I've done in the past this means the mods size will be larger than I prefer and it may even cause some issues on lower-end machines.
The good news is I don't need to move forward with something I'm new at and can instead focus on identifying missing BGM IDs, sourcing a few more tracks and then splicing loops.