Funds are marked as frozen on Gatecoin when:
1/ We are currently double checking a fiat currency credit that you have made
2/ We are currently performing the fiat currency withdrawal that you have requested
3/ Our cryptocurrency transfer service has located an incoming transaction to your credit address, but the amount of confirmations required by our service is too low for the funds to be available and you will therefore need to wait a little more time before the funds are made available for trading. Please, read more about what is "confirmations" in this article.
4/ You have placed an order that has not been matched instantly, as a result some of your funds are still in the order book and should be taken by a counterparty later.