Yes, it is with an unmodified version of the GoWpfDemo !
It happens sometimes with the Silverlight Demo on your domain (GoSilverlightDemo), but I’m not able to reproduce the exact sequence on the Silverlight version. I will search deeper for the Silverlight version.
And with the others machines, my working partner will answer you here, on this post !
Just to be sure, on my previous post, I said “Zoom in and zoom out” in the second situation. For the zoom in/zoom out, I use Ctrl + Mouse Scroll.