Conflicting theme issue?

Hi again! I've not been having much luck with themes recently it would seem

We originally had some of the more classic themes tweaked for our site (James you know about this - think you did it!)

Things like Cutline, Regulus etc

Recently I download the theme pack and installed the whole thing - not thinking that it would be a problem.

However i noticed that when looking through the theme admin panel, the original themes (that were slightly tweaked) were still showing in the list but I couldn't make them available/unavailable at all.

So i have since deleted the themes by the same name that I uploaded from Farms 100 theme pack, but now any of the blogs in my network that originally showed the default theme are now just showing blanks......not ideal really.

If I go to the admin area of a now blank blog, I can change the theme to another, save it and then change it straight back to the original theme and it works fine :o

Is there a way for me to search my network for all themes using cutline (the original default) and manually change them so it shows a theme again?

If not, is there anyway I can fix this?

Sam