DUDE IM TRYING TO FIGURE OUT THE EXACT SAME THINGS! I'm going insane over it. I feel like there has to be a movement upgrade I'm missing cause I don't get why there would be upgrades, or rooms/tiles I can't discover, and I see Power orbs and defense orbs in spots, I just can't reach them. And skill points. I have skills that exist, making me think im missing skill points, but I don't know at the same time. etc etc.
Screw aqua jets, and my non existent water movement.
The doctor/scientist guy/Birch even mentioned a prototype of the thing that would unrestrict water movement, making it sound like it exists on the map, BUT I HAVE NO IDEA WHERE IT IS!