QuickSilver program not loading

Hi

I am trying to install quicksilver, I followed a youtube tutorial and because the "shelf" feature was not working for me I decided to uninstall quicksilver and re-install it again.
(i un-stalled it using appCleaner)

now that I trying to install it again it gives me this message:
"The previous version of Quicksilver was located in "Quicksilver 3". Would you like to move this new version to that location?"

I click yes. but now the program does not work. it is not listed in the apps folder, there is no result when I search for quick silver, and yet the above message comes up every time I try to install it. - when I install it (after pressing yes to the above message) the program loads up (I see it in the navigation bar) but nothing works, if I try to view the preferences, it just gives a blank window

So can you recommend me something I can do

Or I was thinking, is there a way to restore the system to few hours a go?

Thanks

Moved to appropriate forum and title edited for clarity.

thanks