I have the December Magic Lantern on my card and have been trying to get the "night vision" video.  I set the ISO to Auto and then change the LV. Disp Gain to +5. Occasionally there is a brief change on the display showing the gain, but not always.  The user manual says this gain is recorded on video - but I cannot get it to work.  Any tips or ideas about what I am doing wrong will be most welcome.