After some tests we couldn't use setup anymore. For sample we can install software more that one time but it was no option for uninstall. Or it was uninstall option only - no possibily for the new setup.
To reproduce, try install somewhere and then delete all files manually or delet files manually and start repeair. It is possible that it is project specific.
Do you have some installer switch for registry clean or something else for set innitial computer state state for the setup?