On Windows, you installed a new version of Bommer from the app store installer, and it installed over top of an existing installation of Bommer. When you load Bommer/Fusion 360, the older version of Bommer runs instead of the new one, or it fails to load at all.
Fully uninstall Bommer before re-installing from the new installer. Click here to read how to uninstall Bommer (note: in this case, do not remove the application data files, as they will be reused with the new version of Bommer).
When Bommer starts up, it selects the correct version to run from the available versions; before using in-app updates, there will be one available version, and after updating via in-app updates there will be the current version and a previous version. When the Bommer installer removes the old files it does not always clean up new versions downloaded via in-app updates. It is possible that these files can conflict with files installed from the new installer, causing unpredictable behavior when Bommer starts up.