No, the timing could be easily handled by the GUI wrapper. When the button is pushed a timehack is taken. Any point after that you can compute how long it has been running.
As for how to use PsTools, I suggest you start with the article linked to toward the bottom of the page I linked to, "PsTools Primer".
This would be a fairly simple project for AutoHotkey/AutoIT folks that hang out here. I'm too busy to take it on as a project.