@Walter Schulz:
I'm on Windows and dfort provided excellent manual for Windows too - first link in my recipe.
Additional notes:
I don't have "a few black lines at the top" a1ex was told about.
It's possible to shoot first in non-crop mode, then swich to crop and shoot, but if you want come back - you should restart camera, image gets corrupted, if you just stop override registers.
Dual ISO doesn't work. Despite I compiled it with changes from iso-research branch. If I enable Dual ISO, Auto ETTR ajust exposure accordingly, but regular data recorded to files, not Dual ISO.