So using desert water with winter terrain may cause temperate trees, or even palms, to grow on the shore.
This is not "bad" behaviour in real world. If you go to Norway (north part of Europe) you can see palms growing nearby the sea. All because hot water there (hot stream from central America: Gulf Stream). So if we have very hot water, palms can grow on iced beach.
EDIT: also, I've seen that my values are not included on the latest windows build. Are they already part of the linux build? Will I get a mention in the development team page when they are?
I don't know, but my guess is that your values are kept in pull request: they need to be merged to Widelands by a contributor (someone with high privileges)