I've been watching this lenghty interview with two of the Powers in the Basement developers, where they talk about the development of this and their next games: https://www.youtube.com/watch?v=WDGEt_a_Su0

If you are interested on learning about what went behind the scenes of Powers in the Basement, or the indie game industry, it's a very interesting watch.

By the way, GOG is mentioned at the 2:52:14 mark (the interview was recorded before the game arrived here).