I'm in pan/crop in a clip, and the functionality seems to have frozen or stopped - I pull in and out and the wh hite dashed box moves, but the image in the preview window is unchanged. I saw a video that said something about removing the taskbar at bottom, but there's no image there; as I say the white square moves in and out and I see the position numbers changing, but the image itself doesn't change - I don't know what I did, but how do I get normal pan/crop function back? Thanks for help.