After the smoke test, start the installed app, run the installer in passive update mode (/P /UPDATE) while it runs, and only stop the app 3 s later. Passes when the installer finishes by itself (no "Error opening file for writing" dialog), exits 0, and has rewritten cinny.exe. Refs #1, #19 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5