If you're stuck on the 1st level, the little tiny black rectangle in the top left corner is a platform you can stand on (also you can grab and jump off of the corner of ledges)
This is gonna sound crazy, but those "little, tiny black rectangles" are actually paintings. The idea was for them to look like they were facing inward towards the level, because they're paintings on the wall, but it just ended up looking like that. I like to call it "Bad Game Design."
