I'm fairly new at this too. Are you getting any outputs? I haved a problem with the watchdog not get set the file I started with had watchdog commented out.
On inverting the output is something like this
Setp m5i20.0.out-00.invert 1
Mine is a little different in that I use the 5i23 with a 7i33 and 7i37 card and the hostmot2 driver were you have the orginal hostmot witch I should have used.