Specific countdown timer

I really have nothing but my "English code" and a basic format to help think about it.

Seems like I need a timer module that creates the one per second updates or 10 per second.
Then call the timer using the toggle code.

There is an xla file available here: http://www.tushar-mehta.com/excel/software/vba_timer/
On the site he says - "The add-in exports a class, called clsTimer. The properties, methods,
and events of the class make it very easy for the developer to add time-based features to
her/his application.

The Timer class uses the Windows APIs SetTimer and KillTimer to raise internal events, and has many other
features that seem to be what I need, but his explanation is beyond my expertise. I am
willing to pay this guy the $30 for the xla file, but I need to make sure it will work first.