Hi
Interesting ......... 
Obviously you could use numerous overlay number texts every second but it would be rather time consuming to say the least and is probably the only way using VP per se.
However, here's a possibility you could try......
Go into U Tube and download one of the many timer videos. (Using YTD Downloader....or similar free program)
e.g.
This is the full size image/video but you can reduce it in size and volume using various programs e,g, Irfanview.
The address for this example is...
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This is a 20 minute digital countdown vido, but there are many others.
These count down but that's not a problem as you can reverse the video so it counts up using VP.
Once you have the video downloaded from UTube, add it to the overlay track, reverse it using the speed option and then using the scale option and position settings, position it in the required corner of the screen.
For the clock in this example you could use...
X% = -40
Y% = -35
Scale = 0.2
This will put the timer in the top left hand corner. Building the preview may take a little time if your video is lengthy.
The clock should now play against your main track video. You can easily adjust the start position by dragging the overlay left or right and If the accuracy is not exact enough you can play about with the speed option but in version 3.04 the preview generation can be slow.............
Nat