What new security "feature" is screwing me up now?

[Tom Horsley]

On fedora 19, the UDEV scripts I have described here work perfectly:

http://home.comcast.net/~tomhorsley/hardware/solidoodle/solidoodle-udev.html

On fedora 20, my user script that sets DISPLAY and
starts /usr/bin/RepetierHost doesn't start RepetierHost,
but other side effects of that script do happen.

If I cut & paste the command, it works fine, so why
won't it start from the script in fedora 20?

I changed the script to log stdout and stderr to a file,
and there is no error, it just doesn't start the program :-(.

It is almost like nohup isn't preventing hup and it
is dying in the sleep command before it starts RH.