Whats maximum balance? My bitcoin client is going to be down so I set my max balance to 900 so it wont auto pay me... I might accumilate like 200-300 btc during my downtime (still mining, which btw i just put up another 1.4 GH/s

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you dont need your bitcoin client to be up...
as long as the address you put at db is one of the addresses of your wallet your fine