So you have the right binary, and the xml file you're running works for other people. Very odd indeed.
I'll have another look over the code when I get done with this config file stuff.
[edit]
Nope, cannot reproduce. I've downloaded the full download and used that with the rgirlsx files that came with it, and got a range of ages. And I also used it with your adjuted files and no others, and got a range of ages with that, too.
So I'm not entirely sure what to suggest at this point.