I think I really didn't get your problem.
You could easily use Time and TimeParse for your calculations.
After setting the preferred time format (24 hour display) with
Code:
TimeFormat("HH:mm")
you could do something like this
Code:
Label1.Text = Time(TimeParse("03:45") - TimeParse("03:25"))
wich results in Label1.Text = "00:20"
specci48