I'm testing with the free catalog before purchasing. I deployed the Notepad++ update to a collection that had some systems with an older version of Notepad++ installed. If the update scan and deployment runs when Notepad++ is open, it reports that the installation was a success, and the installer replaces the change.log, the uninstall.exe, and the ARP entry, but the applications Help->About window, as well as the version of the EXE, are both still the old version.