Cant play the game any further, tried restarting my computer to no avail. Steam users say they have a workaround by using "experimental" patch settings. Any hope for GOG users?

A patch for PS4 has been released where this is fixed among other things. The PC patch comes out soon.

Same here, nothing in game seems to fix this. Opening the map and CTD. This is a really serious bug as you cannot travel anywhere anymore.

Experimental beta 1.31 is also available for GOG. The password is: 3xperimental

Thank you, could you please tell me how to access that?

See my screenshot in the other post (although in German). You have to use Galaxy. Go to the game choose preferences from the "More" drop down menu and you should see the page I posted the screenshot from. Switch on "Beta Channel" then you can opt in for a "Private Channel" from the drop down menu below. Use the password "3xperimental" and it should add the "experimental beta" to the list as seen on my screenshot. Wait for the game to update (was about 15 MB for me). Enjoy ... or better hope they fixed whatever problem you have at the moment.

Actually at this moment it works again using the update of the GOG galaxy client - no experimental needed, just update the game (33 MB for me).
Thanks a lot for this hint.