I think the ability to move the position of the "Left menu" to above, below or to the right of the lesson would be desirable.

I currently have several themes in use which restrict the page width, this means that when the left menu is active it kicks out embedded lesson content (e.g. flash) to the right, and also greatly restricts the lesson menu itself. (see screenshot).

Even without embedded content, having the menu positioned to the left or right greatly impacts the position of lesson content (for example image floats and text get all messed up). Being able to move the menu to above or below the content would avoid this.