If the installer is broken, I suggest installing an application which enables you to perform advanced uninstalling. For that purpose Your Uninstaller! is a choice since it has some aggressive ways of removing programs (and safe in the same time) but it will get rid of the problematic applications.
The procedure is very simple, install the software, start it and let it find all the installed programs. Then click on Advanced Uninstall or locate the entry in the main window. You will notice that it will have a yellow exclamation mark which means that it's broken.