Unable to close dialog box

Hi , I am using the Duplice Finder 2 plugin to locate duplicate images in my LR Catalog, it seems to work as it finds duplicates but this dialog box is impossible to close, and I have to use Task Manager to close LR and then all the info on duplicate files is lost when I restart LR.  Tried hitting the cancel button and the X but nothing will close it for me.  I have started a ticket with Jim Keir of Duplicate Finder 2 but thought I would check her too and see if anyone else is having the same issue.