Inna - This is a good start, but it leaves a lot out. How does the user first identify what they are looking for? Is it a good idea to add that step? A traditional signage system helps you find your way without typing in a destination at the beginning. What do your maps look like? How do you address the representation of the double height spaces? How do you choose from several possible paths? What is the difference in visual representation (of the map) on the large, high-resolution display vs. the small hand held display?