Because of the complexity your about to approach, strap in and hang on. What is the tool supposed to do every 10 seconds, that's hardly long enough to let the machine process a single command? First lets use the easier method, and just create a form that does NOT open modal, just use form.show (not form.showDialog). Then the external command can quit, return succeeded. This form should stay open until the user closes it.
To get the timer you need to go to the VisualStudio Toolbox, Components group, and drag the timmer onto the form (it hides at the bottom of the screen). Set the interval on the timmer (in millisecons) in its properties. Then place your event code on the form. (I'm a vb Programmer so bear with me)
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
End Sub
After you open the form, the timmer will continue to tick away until you close the form, or write code to bypass the timmer tick procedure like
If runTimmer Then
'do something
End If
As such you can but a button on the form that affects the runTimmer boolean so that the tick will do something or not.
jvj