Yes Max2D is on top of OpenGL to make it easier to do simple things like draw an image. DrawImage is a lot easier than setting up all the OpenGL commands.
It's up to you whether you write your own OpenGL code or not, but basically if you do you will be replacing much of what Max2D does.
It's up to you whether you write your own OpenGL code or not, but basically if you do you will be replacing much of what Max2D does.