Flat registration when amenities are not ready

Hi Sreekanth, I have booked a flat in Bangalore in 2013. It is an under construction building. Now builder is asking for flat registration. As I am not in India for many years and i have seen the flat progress for many years. When I called the Builder for the flat status via email and telephone then he sent an email saying that flat is 90% completed but he did not say anything about the amenities. Then i told my friend to visit the flat and send me the latest pictures and my friend told me that flat looks fine and builder is correct that 90% is completed but amenities are still in progress. And 30 people are already shifted in the building. Kindly could you please suggest that what is the right time for flat registration. I mean before amenities are ready or after amenities are ready. Is there any penalty if we register after completion of amenities ? Builder also told me that he will give me OC(Occupancy Certificate) after the registration and Khatta certificate later. Thanks & Regards, Kunal Sharma