I follow the courses for Expression Blend. In Scenarios Level 2 Module 6 Movies, there is Lesson01_Assets_Movies.
The instruction is about drag and drop a a MediaPlayer control element into MainPage.xaml.
This fails in my setup. If you click Assets and then select the MediaPlayer it will be added to the toolbox allright. However if you drag the MP control onto the Application window EB either hangs or throws an exception. All other lessons worked so far.
There is a comment from the instructor in the webcast about different versions of EXPRESSION STUDIO components. not sure what it refers to.
I use Expression Blend 4 + Sketchflow version 4.0.30816.0
According to your discription,
Expression Blend + SketchFlow is a better place for you to post the issue, and suggest you post more information on this issue there, e.g. what the specific exception is. Thanks for your understanding.