Thank you for writing.
It appears that the Visual Style Builder is trying to open a theme, which does not exist - in the error message you sent in your previous email, I noticed that the name is VSSBlue.xml, while the theme in the Resources folder of the Visual Style Bulider project has the name VSBBlue.xml.
Please let me know whether you made a typo pasting the error in your previous email, and whether it was indeed the VSBBlue.xml file that could not be found.
If that was not the case, and the Visual Style Builder is indeed attempting to load a VSSBlue.xml theme, do you recall making changes to Visual Style Builder code?
the Telerik team