Not sure if I got this right. Installed it and opened VS2010. Got a menu entry under Tools for Find Results Twek. Click it and get a glimpse of a window that then is gone.
Very odd, I have an idea of the cause (which would be a weird registry setting) so I have updated it to cope with those as well. I have also changed it from the add-in model to the new VSIX model which means I can catch the exception if that does not solve it.
For the last time (hopefully) can you download it again, you should get a VSIX now, and install that. Please make sure you uninstall the old one first (while all instances of VS 2010 are closed).