since the repository's down, is there another link?
Give it a little while ... Repository will come back. It's never down for more than a couple of days - whoever maintains it is quite efficient about that sort of thing.
Last version of Mesoamerica was for M&B .808 - not like anything new is out.
(Honestly, I'm not sure what the latest version was, or if I have backups ... I think my copy had some work done to it after the last public release. I would just post it somewhere, but I'm not sure what to post.)