The other day a customer of MZ-Tools 7.0 reported an exception in the Sort Code Elements feature that after investigation turned out to be a bug of the file code model.

I have documented it here:

BUG: EnvDTE.CodeElement.StartPoint.Line wrong result with duplicated ‘using’ statement.
http://www.mztools.com/articles/2012/MZ2012024.aspx

And I have reported it to Microsoft Connect:

EnvDTE.CodeElement wrong start line for duplicated “using” statement
https://connect.microsoft.com/VisualStudio/feedback/details/765375/envdte-codeelement-wrong-start-line-for-duplicated-using-statement#details