Hi there,
I want to make my own platform game based on the “Creating a Platform Game” tutorial here on Kirupa - see the link below.
I’m using Flash 8 and when I change t he flash player versionfrom 6 to 8 in Publish Settings the game stop working! I have no experience in working with the difference between MX and 8 so I have no Idea of what the problem is. 
Can anyone give me an answer to this?
Platform tutorial:
http://www.kirupa.com/developer/mx2004/platform_game.htm