I'm glad you managed to figure out a way that worked :3 I don't have a mac myself, so when people tell me all the different ways they've managed to successfully open stuff, it doesn't mean a whole lot to me >.< I'm not 100% sure without re-reading the whole post, but I think the method you described might already be on the list of things to try that I just linked in my reply to the above comment. If it's not, I'll add it to the list when I get a chance.
I have no idea which steps are the most useful/likely to work for the largest number of people >.< but everything on the list has apparently worked for someone at least x3