I'm sending clips from FCP to motion to use the time remap function in the properties tab of the inspector and when I change from constant speed to variable speed the picture drops out and becomes black.
The footage is shoot in HDV and is also backed up using pro res 422hq. When I send the footage compressed with either codec the same thing happens.
If I import the footage directly to Motion then the time remap function works properly with both condecs.
I've ran into the same problem. Just one DVCPro HD 1080i60 clip with no filters or time remapping applied. Select clip and send to Motion. In Motion I change from Constant Speed to Variable speed and the clip disappears. Change back to Constant Speed and the clip re-appears. If I import the same clip directly into Motion then it works like a champ. I have no idea as to what is causing that. The Set Speed behavior is awesome and works either way.