Hi there,
I don't want to open a new topic, but I have the same Error on my 50D when I want to shoot RAW in Crop mode.
As soon as I am in crop mode and hit the record button, it shows me the "RAW DETECT ERROR" stuff and the green RAW in the info bar on the bottom of the screen turns into a grey RAW.
RAW shooting in normal mode (not crop) works great.
I am running the "magiclantern-Nightly.2016Aug24.50D109.zip" firmware.
Cheers,
Kate