Could it be possible to get a changelog for 1.06 as well since the game seems to have very recently got that update?

Weird that there's no changelog, here or on Steam, for 1.06.

But here's the changelog (according to the Steam forums) for 1.07, at least:

1.07
- General optimization (framerate, memory, load smoothness)
- AI character triggers adjusted
- Fix for rare button prompt conflicts (bike unlock, stereo unlock)
- Save state fixes (dungeon buttons)
- Fixed conversation that warped bike to invalid location
- Animation fix (rock face)
- Fix for errors regarding dancing enemies online
- Fix for tracking of "Tour de Penfurzy" trophy
- Z-fighting fixes
- Pause screen closing on controller removal
- Minor text fixes

Unsure if GOG received any specific changes, though...

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