CropUrl should be formatted with InvariantCulture.

When "Culture and Hostnames" is set to "nl", the crop url contains commas where it should contain dots. As a result the cropper just wont work.
 
E.g.:
language = nl –> /media/1015/kantoor.jpg?crop=0,50926279359747528,0,44275147434918666,0,10902867903402354,0,37051178879082175&cropmode=percentage&width=775&height=284&rnd=635310800525781037

language = inherit –> /media/1015/kantoor.jpg?crop=0.50926279359747528,0.44275147434918666,0.10902867903402354,0.37051178879082175&cropmode=percentage&width=775&height=284&rnd=635310801460824519