Same problem, I'm afraid, even after force-uninstalling the older version with Wise Program Uninstaller! It gives me an error about not being able to stop TileGraphX, almost like the installer is complaining about itself being open. It did that before, too, but it'd only give me that particular error when I'd install it for all users and not just the current one. I'm headed to bed now, but I'll try again in the morning and record it in case that helps you figure out what's going on.
I'm really looking forward to playing with this!