I have done a pretty good search on the site and I haven't found a topic for this issue.

How do you get the autopilot to carry out the descent plan you program in the FMC?  Something tells me that I'm just forgetting one simple click, but everytime the aircraft reaches the Top of Descent, the autopilot continues to maintain the cruising altitude.

Is there a video or pic tutorial somehwere that covers descent procedures with the FMC and autopilot?