Have you, by any chance, changed the time on your device (perhaps to speed up game play)? The game relies on the accuracy of the device's clock to operate properly. Unpredictable results can occur if adjustments are made to the clock. We have never seen the game get 'stuck' in either night or day, so I cannot tell you how to correct the problem, other than to make sure that the device's clock is always set to the correct time. You can manually switch between day and night by using the "Reverse Day/Night' setting on the Options dialog.

By 'art' are you referring to the game icon? If so, I have seen that situation occur on other iPhone applications (although I've never seen it on our games - it's usually after I've installed very large applications), and it appears to be a problem with the device's handling of app installations. When I have seen that issue, the problem has resolved itself after a few syncs with iTunes and/or device resets.