Removing the ICSharpCode.SharpZipLib.dll did resolve the file manager error and I don't get build errors, but now when you try and access images, files, media, etc from the CE toolbar you get the following error:

 

Could not load file or assembly 'ICSharpCode.SharpZipLib

Version 0.84.0.0, Culture-neutral,

PublicKeyToken=1b03e6acf1164f73' or one of it's

dependancies.  The system could not find the file specified.

 

Hope this helps.