The approval by RERA is likely to be delayed but that does not mean that the builder will start constructing the project without approval.
In any case without any sale agreement it is not advisable to make any further payment.
The builder should not and may not be able to enter into sale agreement without the approval of RERA or even the commencement certificate.
If the property falls within the panchayat limit, what is the CMDA approval doing in this, did you see the copy of the CMDA approval?
What is the approval sanctioned by CMDA?
You may don't accept the rental amount under the scheme, it will be deleterious because after one stage if the builder stops paying the rent then you may not be able to claim it neither the bank or court will come to yor rescue in case the builder defaults.
The bank will approve the loan but it will directly disburse the amount to the builder, in that case in case of any default in future you would be liable to repay the same and not the builder.
Further it is not common that the RERA sanctions approval but not allotting the number.
Once the RERA is approving the project, it will pass the orders with the proper details.
If you feel that this project may not be viable or feasible then you can cancel the booking and claim full refund