Builder not ready for completing basic needs of society

I am staying in flat from last 6 months society has 4 building which consists of total 220 flats. society area is not under Municipal corporation it comes under gram panchayat where few things are necessary like Sewage treatment plan, water softening system, good lift, rain water harvesting and amenities. society is 70-80% occupied now and many people have taken possesion at different dates everyone has given 1 years maintenance amount in advance. builder is saying 2-3 lakhs rs are going every month for disposal of Sewage water through tanks as STP is not ready and not upto requirement. few queries: 1. can builder use maintenance amount for such basic things likes stp, rain water harvesting, water softening plant and amenities like gym etc? 2. STP (Sewage treatment plant) plant is not upto mark or has very limited capacity and because of which 2-3 lakhs rs are getting used in disposal of water. does this amount can get consider under maintenance amount? 3. amenities like gym and library are not completed yet.. what if we does not provide sufficient instruments for gym or stationary and books for library. is there any standard like number of instruments he should provide for it. 4. what should get consider under maintenance amount as builder can use this amount for completing basic needs and what amount should not get consider under it 5. how can we fight against builder if builder is not ready to provide proper amenities and does not complete work according to 220 flats. what can we do if stp has less capacity as per flats number