Yeah, I'm finding that too. For example I got to the place where you start in 8 after traveling through 6 for a while. Also I spent a while in 4 and now think I understand how the buttons work (using Enter). After traveling through 6 for a while I got to a place, after going up and then all the way to the left, where there was a button and what looked like another path through the door, but I couldn't go anywhere after going through the door. I also think the the 'dust cells' and 'dust particles' count in 8 are connected to what you shoot out when you click (so I guess you're shooting out dust), but I haven't been able to figure out the exact relationship. Also I noticed sometimes there are purple orb things that you can pick up, but once you've picked up a bunch of them then you can no longer pick up new ones - but I can't figure out what they do either!
okay so, I went back to the game because it'd been a while. once you press 6 and get into the world with the little flying guy and you go to the left, and then up, you'll end up beneath a sort of cube structure that seems like you can't get past it. But after just flying into it a bunch and pressing enter and clicking I sort of... sort of teleported through it... I'm not sure how to replicate it. Then to the left from there I came across a room called 'water chambers'. And to the right from there I came across a room with a big pyramid, and after traveling up through the pyramid the pyramid I ultimately ended up at the screen where you start on if you press 8. that's about as far as I've gotten. I feel like there's definitely more to unravel, but I haven't made any progress.