So I went ahead and moved all of the COD files of the themes I don't use, and now I'm limited to "none" for my theme (it won't let me activate my nice vodaphone today theme).

Anyway, I'm trying to get this back by to reload one of the themes at a time - and it's very time consuming. It's pretty clear that at least one of those themes needs to stay on the device, but does anyone know which one it is?

I will post my findings if nobody gets to it before me.