Mark,

if the system needs a reboot after an uninstall means that one or more files were locked (in-use) during the uninstallation process. The only way to handle your specific scenario is to check in your (custom) uninstall if all files can be removed. You could handle this in a custom uninstall script by using "Check In-Use Folder Tree..." and "Check In-Use File...". And it's always a good idea to see if your main application is not active - you can check this with "Detect Active Application...".

To sum it up: only continue with the uninstall if the main app is not active (not running) and the files can be removed.

Does this help?

Friedrich