I’ve found an easy way to create these timers in Bolt, they come in handy for many kinds of games. The timers start and stop with bool variables and updated a text with the current time counts.
Count Down Timer

The count down timer starts when the Countdown_Timer_Running variable is set to true the timer starts counting down from the Timer_Count_Down integer variable which is set in seconds (120 = 2 minutes). When the timer hits zero it stops running.
Stop Watch Timer

The Stop Watch timer starts when the Stopwatch_Timer_Running is set to True. and start counting up in seconds storing the full time passed in the Stopwater_Time Integer variable.