Hi ovaflo,
There are no bugs regarding this in the Mac version, it works fine. I think the problems you are having are because you don't quite get how the cropping works. Some what counterintuitively, to my mind, the crop origin is in the bottom left hand corner with coordinates increasing bottom to top and left to right.
Both of the crop areas that you've defined cover the same area. The difference in them is that with one you've got the top lower than the bottom. TG2 doesn't check to see if you've kind of "inverted" the crop area.
Stick in these values :
left = 0.5
right = 0.6
bottom = 0.5
top = 0.6
You'll see that a small area in the top right quadrant of the image is cropped out.
I personally think the way the crop definition works is very poor, it's the absolute basics, it works but it's awkward, and we will be adding crop regions you can just drag around on the 3D Preview, and hopefully multiple crop regions as well.
Regards,
Jo