While it shouldn't be hard to navigate your way through the initial release of STELLAR INCOGNITA, I'm including 3 walkthroughs that will be updated and expanded on as the game is updated.
There are three routes (A, B and C), based on the first decision screen in the game. Refer to the walkthrough that corresponds to that first decision.
Finally, why does it look so odd, with so much negative space? Well, that's because at the moment, there are hardly any parts of the jigsaw on the table. As the game is updated, all that negative space will be filled in with extra decision tree branches.