Inappropriate cancellation charges by builders even before agreement is signed

I see different answers by experts on the booking amount cancellation charges which are typically 2% sale value, even before the agreement of sale is signed. Builder has taken 10L out of which 4L booking amount, 6L to ensure that the reason requested by buyer for additional time was genuine. After 30 days he sends an email that the allotment is cancelled and refund will be done as per the booking terms and conditions, and allotment can be carried over only if customer agrees to pay additional 200 per-sft, which customer didn't accept. It has been 100 days over post this email and builder hasn't yet refunded the amount. In spite of multiple reminders and visits, he simply kept on delaying and when customer indicates that he has no option than serving a notice, builder is threating to deduct 2% sale value with 2.8 lakhs. Builder is not providing signed booking form. What options do the customer have now ? He never wanted to cancel the booking. When he asked additional time, they agreed and took additional amount to be adjusted as part of final value, after 30 days of last payment they cancelled the booking on their own with a demand to pay more per sft. It is obviously a gimmick by builder to loot customers and why would any arbitrary conditions be imposed in the name of booking cancellation ? He has allotted the customer flat to others and got booking amount. Where is the loss made to builder ? Which rule supports him holding customer money for more than 100 days ? Why builder is not returning the copy of booking form? Can we proceed with criminal case of cheating or the consumer court only option ?