Citation from manual: "DISP presets: 1..4 -> To change the presets, press the Metering button. -> What button ? In 550D there is no such button"
But there is no metering button in EOS 550d, so I am unable to change disp mode. In version: magiclantern-2011Apr30.550d.fw109.fixes.alex it was changed by DISP button.
I suggest to add ML option to set which button should be used : DISP/ MENU / SET/ AF point selection .