If you have done this update then you have to look to see if you have two versions of EZdrummer installed.  You might have installed it once in the Cakewalk VST plugins folder and then later after doing deletions or restores you might have installed it in the C:\Program Files\VSTPlugins directory.  If Sonar is pointed at the wrong version, then you have a problem.  But it's an easy one to fix.  Change the name of the oldest version to ezdrummer.bak and see if EZdrummer 2 loads the correct version.  If it doesn't then go into the Plugin Manager and browse to the newest version and see if it loads the newest version with the SONAR Options.

Dave you have done a great job in getting this problem fixed for Konrad. Thanks for not giving up.