When I played this game on Gamepirate.com, I found that one thing that could apparently trigger the dreaded -NAN issue was if you "upgrade" any booth or facility that was already a 3-star. I wonder if this can still happen now?
To the one who said that the maker of this game needs to learn grammar, please understand that English may not be that person's first language. Japanese is probably that person's first language, especially since that tutorial girl looks Anime-ish.
Cephlapod -- thanks for the heads-up on King.com! Here's a VERY good reason to hate lots of ads on a Website: it makes it more likely that at least one of the ads could contain a script that redirects the browser to a Website that downloads and installs some sort of malware. Malware such as the Zeus trojan, rogue security software (eg. Antivirus Live, Vista Antispyware 2010, etc.), and adware.
As for the game itself, it's awesome, as is apparenly any game with Berzerk's name on it!
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true, we already fix it now.