Now the Mac version is gone suddenly... possible to get money back?
Or is the Mac version in pipeline?

did you try wineskin or portingkit port?
in an interview, in german let's play community one designer of the game stated that they won't provide mac support in the near future due to the small team and resources.

Then why did gog announce the Mac version? On itch.io you can read, that Mac OS was planned:
https://toukana.itch.io/dorfromantik

* uploaded improved, tested Mac build, does not work on some systems
* added Linux build (untested)

They worked on a Mac and a Linux version...

interesting point. In the interview he said they now just concentrate on windows version. In steam it says they had mac demo but too many bugs around, that's why they just focus on windows first.

That´s right we ported our very early prototype to mac and linux, but encountered some problems we weren´t able to reproduce and therefore fix properly. That´s why we decided to focus fully on finishing the game for windows. We´re sorry if there was wrong information somewhere around here, but it´s not planned to provide a mac version in the near future.
So if you are not able to play it now, feel free to refund your purchase