"Crop" produces all-black video

Maybe I'm being dense about this... I am using Fedora 14, with kdenlive-

Any time I try to use the "Crop" function, even 1 pixel, the whole video window blacks out. I tried rendering a short video to see if it were otherwise in the rendered version, but that is all black as well. Maybe I don't understand what it is supposed to do -- what I want is to "focus" the video on one small part of the image, blacking out the rest.

Any suggestions about what I can do/how to properly understand Crop?


I would use the scaleOtilt effect in your case.
I've never had any trouble with that tool, except of mixing Clips with/without interlace.

If you still in trouble, it would be useful if you could setup a small example project and post it.