I got mine in the mail on Saturday! Thanks busman!
Here's how I got it to work.
Set the time. As you advance through the options to set, you come to the ALRT setting. Change that the VIBE or COMBO.
Now, finish setting the time. To get to the Timer,
1.) hit MODE 2X.
2.) hit set 2X. The hours will be flashing.
3.) Hit NEXT 2X to get to seconds and put in the time in seconds you want.
4.) Hit SET once more and you will see TIMER and the amount of time displayed. When this is on the display, just hit START on the upper right and it will countdown. When it finishes, it will vibrate!
To reset the Timer, just hit SET/RESET once and it will go back to the time you set. (I originally did this by a longer route, but I was using it in a game and found this MUCH easier way). It is awesome!