I used to use either IE or FF as browser for initial test. I recently moved to Google Chrome. Google Chrome does not give a range of errors for flash.
For example the error below comes up in IE whilst Chrome simply does not work:
*Error: Error #2176: Certain actions, such as those that display a pop-up window, may only be invoked upon user interaction, for example by a mouse click or button press.
As I was used to IE telling me this it took me ages to figure out what was going wrong.
Just figured I put this out there in case it happens to someone else.