Thanks - you are right, I had Grid.WPF45 installed and not the latest version of SfGrid.WPF45.
However I can't get the latest version of SfGrid.WPF45 from your nuget feed - the latest version on there is 18.104.22.168
I am getting the feed URL by logging in at http://nuget.syncfusion.com/ and using the URL from the "WPF" section.
I have tried manually pasting in the packages in your test project (from packages.config) but nuget then complains it cannot find the right version.
Could you update your nuget feed and I will retest with the latest version.