Hi Henrik -

If you are not aware that Ninox uses miliseconds since the Unix epoch to do all datetime calculations. So to add time to a date/time field you have to take the data in your 'Traveltime in min' field, which is probably in human readable form of a positive integer, and multiply it by 60000 for min or 3600000 for hours. So you code would look something like:

time(departure+'traveltime in min'*60000)

I hope this helps. Let us know how it goes.