Driving Distance Calculator Widget: Limit the widget to search only on user defined locations

We offer airport transfer services just in Spain and Paris. I keep receiving quotes from people where we don't operate. Because the distance calculator widget I am using shows global locations. Is there anyway I can limit the widget to search only in Spain and Paris where we operate? If yes how can I do it?

That's not currently possible on that widget but I will escalate this as a feature request so it will be considered in the future updates.