No worries, I quite understand that
That is a really fiendish puzzle, yeah -- Lars (Fiskbit here) is known for those. Bear in mind that you can still emit a stream from the locked blocks, you just can't rotate them. The solution is to figure out which block to start from, once you figure out which direction to point the locked block. If you haven't yet solved the advanced tutorial with the U-Turns, then this puzzle would be even harder. Let us know if you want another hint. I can't solve a number of the puzzles in this game, but at least this one I can.