Good job :) I like the vertical design and acid idea. The legend is nice, though it does get a bit confusing with the amount of different colors an how much I have to remember. Combining both shapes and colors might be a better option with this much information (And using the colors for connecting switches and doors/platforms).
The level does feel a bit empty though. I would consider populating it a bit more, as it is it feels just a bit too short.
For the end of the level - I would consider if it's needed to jump into the small opening? It feels a bit anti-climatic and suddenly very crowded. I would be fine with just rising to the victory on the moving platform. And maybe adding these small alcoves that the player needs to jump in while the platform is moving to avoid obstacles in the middle. But that is more of a personal opinion.
To return back to the one page design document itself. I'm still trying to wrap my head around the red dots and their purpose. Do they tell me, the reader, something? Or are they there to help you, the creator, with the designing process (In which case I wouldn't include them in the final paper)?
You also have plenty of empty space both in and out of the grid. Don't be afraid to use that. For example - what is the range of the spitters?