While in the shop, I clicked the map button in the upper right. The UI for the map was invisible, but the shop remained. I could roll over areas of the screen and get the pop up text about the region/who controls/etc. The main window for the shop still remained where I could look at the drill down on the left, and the options within each drill down. However, no way to back out of either UI was available. Had to alt/tab/delete to exit the game.