Try this version. It works for me whether a movie exists or not.
Track Delay (account for movie).kmmacros (55 KB)
If it doesn't work for you, first disable the Combined Script group and enable the Separate Scripts and test that. If it still doesn't work, send me the AppleScript output from the UI Browser Lite macro while hovering over the Delay field. That should hopefully show me any discrepancies between our screensets.

