I have tested other Silverlight applications (which works without issues). I have upgraded Silverlight to the latest version. The strange thing is that the developer console is completely empty - there is absolutly no error messages.
Then it continues forever without showing the application. I suspected this was realted to ClientUI, and when I try to run, it doesn't work on any of the Macs. However, out application doesn't seem to work on Macs.
One client is about to change all its PCs into Macs. We have a Silverlight application built on ClientUI controls a couple of years back.