Creating Tasklist/Checklist

Howdy,

I use a simple Excel 2007 sheet to manage a somewhat time-sensitive checklist. The list now has over 1200 items that must be accomplished in a 24 hour period.

What I would like to do is have the row start flashing red when the event is supposed to start, and then stop fliashing when a checkbox is selected, or a dropdown is selected. Attached is a sample.

Thanks for any help.

James