Install: uninstall other builds first (over a previous ayaka build is fine), then sideload.
Use: open app → set Min / Max Aspect → Start. Raise both = zoom in, lower both = wider (default 0.75 / 1.0). To change later, close the game and reopen the app.
Even with CDN cache OFF, packs already on disk (archive.org pre-downloads and installed-mod packs) are now served by the server itself — offline play and modded data work; only genuinely-missing packs go to the CDN.