I am resurrecting this and i ask your forgiveness, but i think i have to post this.
If you bought the game trough Humble Bundle, you could link your game to a steam account, i don't know if Tynan is allowing that for GoG (i personally don't own that version) so it would be fair to ask him in the forums or through Ludeon's costumer support if he can do that.

And a free advice as a former player since A15.
You don't want the latest version of any mod, what you want are working versions of the mods in your current colony and stick to them till your bitter downfall (usually a FPS death).
The only reason to update would be if a bug is fixed, but you shouldn't play buggy mods anyway, and even then, it is not unheard of of updates completely shitting on your save files, so it is better if you go for the enterprise approach when updating, and only do it manually with tested, mature updates. So getting the mods through Rimpy and making offline copies, is for me, the best option to get Rimworld mods.

How does that work? How can it import Steam mods to Gog Rimworld?