Mac claims that a newer software version already existsWatch
So put it in the trash and cleared trash (didn't realise it had an uninstaller) but it's all gone anyway. Searched in finder, no remnants of the application was remaining.
Now, i downloaded an older version (not from the official site, blocked over here) but can't install because each time I try to it says a "newer version of the software already exists on disk"
The app's preferences file may be conflicting with it, as the .plist file isn't always stored with the application. Go into Library>>Preferences (You may have to make Library visible if you're using Lion, a guide to doing so can be found here), and scout around to see if you can see anything from the old application. Clear that out, then try installing again.