PeterS wrote:if it is an X app it might even run in X under Mint.
Very likely, but i wouldn't recommend that. Although X works under Mint, it is awfully slow, and i think there are very few users which have it installed. XTide seems to have been ported already to Windows & MacOS (although not available on that site), so it should be possible to port it to GEM, too. If you are really interested in that program, a GEM version would be much more convenient. But of course that will depend on the amount of work needed to port it.