Hello,
Did you ever find a way to get the .dmg file to install? I've been having this issue for the past week, and Epson thinks it's an OSX problem. I'm also using Snow Leopard. I spent the $50 to talk with an Apple level 2 person, we did some maintenance, but still not able to get the thing to install. ( I should mention it loaded on my newer laptop, but my desktop is what I print from.)
Any help you can offer would be greatly appreciated.