So you bought a
property under the old deferred payment scheme.
You simply just sell it. Get someone to offer to buy it, accept the offer, the lawyers take over and there you go, property sold.
Hopefully, you will be able to get a price of at least what you paid for it, or higher. Possible in today's market depending on when you bought it, and which development it is. Buyer pays 1% option fee to get you to sell them your property, then pay you another 4% when they exercise the option. Thereafter, the lawyers can do everything.
Now if you can't get a price that at least matches what you paid, the answer to your question of 'how do I get paid' is 'you don't get paid'. You have to make good the difference to the buyer since the developer expects to be pad whatever price you bought the unit at. The buyers' lawyers will not complete the sale when they find out this is the case.
Or you really could sit back and do absolutely nothing till TOP, and continue to do nothing thereafter and hope the developer manages to find a solution that is good for them, and hopefully for you too (unlikely since you both have diametrically opposing objectives). Just be aware that the developer has a million ways to shaft you if you read your S&P agreement carefully, and not vice versa.