summary
Windows troubleshooting marathon: OneDrive confusion resolved (not installed), duplicate Downloads traced to Google Drive cache, .bat file association fixed, Start Menu category-view fully resolved via Start11 after 3 failed attempts, Blu-ray drive logged on separate machine (DavidsLaptop), platform catch-up completed
work_done
Fixed broken .bat file association (K330); diagnosed and closed OneDrive not-installed mystery (K325); traced duplicate Downloads to Google Drive temp cache (M0021); researched and confirmed Start11 as working Start Menu fix after WinUtil/registry/StartAllBack all failed (K336); flagged Pictures 1 photo library as do-not-delete pending backup (K329); logged Blu-ray drive + researched free burning software for DavidsLaptop; resolved 3 blocking platform pickup items; added Build Diary backfill task to todo