Jack, from Walmart to Chi Chi's is a straight shot up the hill on the main road into Escazu. At the cruce where Scotiabank is, continue straight up, don't go right toward Santa Ana. From there maybe 1 km up, on your left side, just before the curve where you must go right. A block before you get to Chi Chi's you will pass the Argentine steakhouse Novilla Alegre on your right side.
Parking is easy unless there is a big soccer game. Then indeed the place is packed with locals and it is a great atmosphere to watch Real Madrid/Barcelona for example. The owners Albert and Danny are great guys, Americans from Miami of Cuban descent. Bilingual and welcome everyone.