Thanks Wendell, I ended up getting this working before seeing your post, not sure exactly how this works, but I stumbled across it somehow:
curTick = TimerTicks (millitime)
If curTick >= newTick
newTick = TimerTicks (milliTime)+1
timeSec = timeOriginal - curTick
timeHour = timeSec/3600
timeMin = (timeSec/60) Mod 60
timeSec = timeSec Mod 60
EndIf
timeStatus$ = timeHour+"Hours, "+timeMin+"Minutes, "+timeSec+" seconds remaining"
curTick = TimerTicks (millitime)
If curTick >= newTick
newTick = TimerTicks (milliTime)+1
timeSec = timeOriginal - curTick
timeHour = timeSec/3600
timeMin = (timeSec/60) Mod 60
timeSec = timeSec Mod 60
EndIf
timeStatus$ = timeHour+"Hours, "+timeMin+"Minutes, "+timeSec+" seconds remaining"