Posted October 17, 2018
They have mentioned more in the comments section:
"We'll definitely be trying! I'm contacting both Itch.io and Humble for a response on this. We'll TRY and get on GOG but it's up to them! We'll update you with an answer once we have it. Give us a few days to figure it out then we'll respond!"
"Ok we've checked. The steam version itself is DRM free! This way you'll be able to do things all on a single front! Gog is going to be quite hard to get onto, they are quite picky."
"We'll definitely be trying! I'm contacting both Itch.io and Humble for a response on this. We'll TRY and get on GOG but it's up to them! We'll update you with an answer once we have it. Give us a few days to figure it out then we'll respond!"
"Ok we've checked. The steam version itself is DRM free! This way you'll be able to do things all on a single front! Gog is going to be quite hard to get onto, they are quite picky."
Post edited October 17, 2018 by WinterSnowfall