You need to talk to the Realtor on site or the developer. Some allow you to transfer your option to sell and some don't. You may have to find someone to be an accomodating mortgagor on your loan and help you buy it, or lose your deposit.
I tried to transfer the option to buy on a condo in Waikiki from a husband to his wife, and they said it wasn't allowed. We had to find a new buyer to buy with him and we put the title in her name.
Let us know what you find out! I hope you can transfer your option.
You may also be able to come to an agreement to only lose part of your deposit. Be sure you are totally released from your contract and get a guarantee in writing.