This was not working for build 808 and then started working for build 809 so I thought it was a bug that was fixed in 809. Then I updated my video drivers and it starts failing again. So I start reading the bugs forum and it seems others had the same problem. I found one suggested solution - trying a diff video rendering overlay - I picked force RGB - it was in mode 1 - not even sure what that is. I'm a total newbie to this. All I know is it worked. I guess I'm wondering if the force RBG overlay setting is appropriate to leave permanently and for all cases?