Overlay Countdown Timer

[Brendon Bauer]

I'm creating several movies that will play before a church service begins. Usually we just buy countdown videos.. but this time I thought I'd get creative and make some. There is always a countdown timer that starts at 5:00 and counts down to 0. This way people know when the service is going to start, from 5 minutes out. I have been searching and searching and cannot find any way to overlay a countdown timer in iMovie HD or iMovie '08 (I have both). Can someone suggest something? I don't want just a countdown movie... it has to be only in the corner or something. I want to use some footage of driving to church, make it fast forward so it finishes in exactly 5 minutes, and have a countdown timer display overtop of that in a corner.

Any ideas? I've tried using the Slick 5 Gallery for iMovie, but they just have countdown movies, not overlay. Also, the Labels & Overlays from stupendous software has a timer, but it only counts up... lol.

HELP