Hi sorry about this extremely late response but I only got the email now. Ok what you need to do is open a new terminal window and type in:
chmod a+x
Put a space after it and then drag your command file into the window and press enter. This should allow you to run it.
By the way, I just changed that slightly so it runs off my desktop and made it into a .command file to make it easier for me. Thanks for the commands though.
I have the same problem with my mac, however i cannot find any way of getting Java 6 to work. Any suggestions? I can load the launcher but when i click login i get a white screen. I used to fix the problem using Java preferences but this has now been removed so i am unable to do so. Please help!