Are you talking about the hall of ascension? What I did was after I close the windows, I waited for the first window to open before raising the platform, its not about the timing of the jump, its the timing of when the platform falls down
That took me about 15 tries, seems the platform blows higher or lower depending on where you're standing on it. Seemed if I was too far forward it didn't go as high. I stood back & in the middle, did a timed run jump and almost flew the whole way up to the ceiling board.
If it jams, force it! If it breaks, it needed replacing anyway