4.9999 out of 5, the symbol puzzles were almost too difficult and some of the objects and rooms were not intuitive to find (resulting in some click-finding)
Minor interface annoyance - when going into buy or upgrade, the cost of the next available item should be highlighted. Currently, you have to click on the item you want, and then go over to the right and click on 1 to see the price.
Sorry, finally found the menu option to pick the level. But after failing a level, you should get to restart on that level instead of having to backout to the menu.
Having a solider who has been promoted to a lieutenant should count as having an officer for the purposes of directing fire and calling for air support.