I've never actually found that a script works properly if you re-load without quitting and re-starting Rome. Have tried the bit you quoted and with the press help when quitting thingy too.... Hopefully someone who has got it working can explain in words of one syllable!
that would mean you're running it as a campaign script and not a background script - I think that is one of the known side effects -
http://forums.totalwar.org/vb/showthread.php?t=46738
you can use a campaign script activated from desc_strat to launch the background script but you won't be able to save until campaign script has terminated.
I found that and anything time related like the wait commands wouldn't work from inside a monitor_event (or if they did half work they spread the event commands over multiple turns!)
it does work for me though if used in a non-monitor if statement eg
if I_TurnNumber = 0
.....
or if in monitor_
conditions
not event