I think you don't have enough Ram to use the theme. To free up some Ram just try closing down some other programs such as true transparency. And just to let you know it is not compatible with winodws vista.
P.S. For future posts try giving more information about your problem and some info in your computer as it will make saving your problem a little bit easy for all of us. 
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Your Toast Has Been Burnt, and No Amount Of Scraping Will Remove The Black Parts!