what does this mean for the coins that I had deposited??
The coins are at the address you sent them. There is an issue in strongcoins backend which is causing the site to display the wrong (0) amount. The coins are are "there" strongcoin simply isn't "seeing" them. No error on strongcoins end can make the coins disapear or be lost (if you have a backup of the private key(s)
how do I find the private key?
In strongcoin click on the address. Then on the right hand side there should be an option "decode private key". The value it shows once you enter password again is the private key. Don't lose it, don't let anyone else see it, don't decode it on a shared computer. Treat the decoded private key like you would cash or gold. Whoever has it has access to the coins. If you lose it = nobody has access, if someone steals it = they have access.
The private key is what allows you to move/spend/transfer (all the same to the network) coins. In Bitcoin the coins are everywhere on tens of thousands of nodes. The private key is what ensures only you can spend your coins and you can't for example spend my coins.
If you make a backup (like printing it out) even if Strongcoin can't fix the problem you can import that private key into another wallet and gain access to the funds.ALWAYS ALWAYS ALWAYS ALWAYS and ALWAYS have a backup of your private key(s).
If it were me I would:
1) make a backup of private key (print it and leave no decrypted copies on your computer).
2) wait for strongcoin to fix their accounting issues.
3) if strongcoin can't fix the problem then import the key into a new wallet/exchange (like say the default client or MtGox account).
Yes I used the
public key public address on the strongcoin account page..
Then you should be fine.