backup your wallet.dat and delete the whole appdata folder. put your wallet in a new location.
i just did it again. left only wallet.dat in the folder. blockchain download allready passed the block of my coins, but still 0 coins
CoolCoin.exe in a new location, and then patiently wait for the update.
just to notify: I installed the wallet on different machine.....let it download the blockchain, and than changed the wallet.dat......still wallet shows 0 coins....hope that next update fixes this