Changelog for Patch 1.15 (added 31 Auguts 2017):

* The Mac and Linux versions will be updated ASAP *

- Updated the majority of the graphics in the game.

I don't use Mac or Linux at the moment but i'm curious if those versions were ever updated or not.

Concerning Linux the installer script is gog_gateways_2.0.0.2.sh and the game
gives version 1.13.

So it seems to be not updated in recent years ...

But using "Microsoft.Xna.Framework" as visible via error messages
(see forum post "Solve "Exception: System.TypeInitializationException - System.Console" error
 under Linux") care for a Linux port is not very likely (there are exceptions like SpaceChem).