When I go offline, the 'browser' link just takes me to all downloaded songs, in song name order. This is hard to work with - there must be something obvious I'm missing. How can I access downloaded songs grouped by artist?
In your music folder, are all files in the same folder? For me, the browser does show songs grouped by original folder.
Yes, all mp3 files are in the same folder, with artist and song name as meta data.
My root issue may be that I just don't really understand the software (e.g. cache vs. permanent cache). Is there documentation somewhere?
When in offline mode, you're presented with the music in the same filesystem layout as if you were Browser mode.
The app is based on this project - https://github.com/daneren2005/Subsonic although there's not a great deal of documentation...