I had the block 15553 problem even after deleting everything but conf and wallet files and redownloading the blockchain. Tried .conf posted by thekidcoin to no avail. Using newest wallet version.

Issue resolved by deleting all but .conf and wallet.dat, restarting comp, renamed .conf to fluttercoin.conf (not sure if this filename matters or if just file extension and location do. couldn't find answer with brief google, anyone know?) and redownloading blockchain again.

This is the only coin I've mined other than a bit of litecoin from a pool to learn the very basics. I'm not sure if what I did would/could have fixed the issue, but it might be worth a try if you're still stuck.

edit: Also remembered I hadn't changed rpcuser and rpcpassword to username and password until the final time I tried downloading the blockchain. Not sure if that matters either...