As far as the time goes, it's not meant to be midnight at the temple, but
whenever its midnight where Ranma is.  

Cool! Ranma could get a plane and fly around the world again and again
so he never hits a place where it's midnight! The whold family could
join in, too!

Actually, all he has to do is wait until it's 11:15 PM on the specified
day, then go over into the next time zone (where it's 12:15 AM on the
following day). Then, his troubles are gone forever. :)

Hey, even better! Then it'll be past the specified time, so Death doesn't
have a hold on Ranma any more! Then Ranma and Akane could live happily
ever after... (Or sacrifice Shampoo to Death and live happily ever after.)

Kun-chan...