Specific relief

Sir: I am a plaintiff (vendee) in a specific performance (of land sale agreement) case (Karnataka) since 2004. A non-alienation order is in force.We have since added as defendant subsequent agreement holder. I now have the following questions: a) Is it absolutely necessary to make subsequent purchaser / subsequent agreement holder pendente lite a party in specific relief case? b) If not made a party will the decree be still binding on subsequent purchaser / subsequent agreement holder pendente lite? c) The new defendant in my case is actually developer and has stated in his WS that he has sold a few plots in the suit land to some persons. Do I need to bring these persons, if WS to be believed, on record? d) The new defendant's lawyer has been delaying my case on one pretext or other...he has completed cross of me and my only witness after many adjournments. What other tricks are available in his disposition to case delay/defraud? e) What can I do to speed up my case which had reached Argument stage years back before adding the new defendant? I request the kind advocates to throw some light on the above. Pl quote citations as appropriate so I may look them up for strengthening my case. Thanks a tonne in advance. Best regards.