Despite the progressive lag issue, I think it's a great game, and one of the few games that I've played to completion (including all achievements). Very good job!
It seems that from viewing the comments, people are not understanding the point of the game. It's not a simulation game, it's a puzzle game. Shoppers will spend their money at the closest store to them. If that store is full, they'll find the next closest store to spend their money. The stores get progressively more expensive, and will make you more money. You have to figure out how to get 100% of the shoppers to spend the most amount of money possible in 20 days.
 "Into Space 2"){kind=icon}
 "Shopping Mall"){kind=icon}