File specific performance of the Unregistered Sale Deed for the sole reason Specific Performance is a highly discretionary equitable relief and an oral agreement is something hard to prove. It's good you have the Sale Deed albeit unregistered that is evidence of the contract.
(Expert) 11 May 2012
I agree with experts.
(Expert) 12 May 2012
Sir/s, With due respects to the Legal Luminaries:
Was it advisable to have lodged the executed deed for registration and issue a notice to the other party to present himself/herself before the Registrar to admit execution. I believe he/she was legally bound to admit execution once he/she had placed signature on a document.