Arbitration clause in builder buyer agreement

Dear Sir I had booked a flat in 2011 and later on the builder cancelled my flat as he had scrapped the tower in which i had booked. After many rounds of discussion he alloted me a new flat in some other tower and asked me to pay extra 5Lacs for the same. I booked the flat and put a case in consumer forum for my old flat cancellation and requested the forum to direct the builder for payment of the extra payment 5 lac taken by him. Please Note: The builder has not appeared in any of the hearings and my case is in final argument. After this the builder kept on demanding the money for my new flat as per construction and i paid accordingly. As of now i have paid 95% of the total cost of the flat. Last month i asked the builder for my statement of account for the new flat and thereafter the builder sent me a letter stating they have appointed an arbitrator as per clause of builder buyer agreement The clause read as follows : " That all disputes or disagreements arising out of , in connection with or in relation to the allotment which can not be amicably settled , shall be finally decided by arbitration and the sole arbitrator in such a case shall be appointed by the company and other provision of Indian Arbitration and Conciliation Act 1996 , or any amendment thereof shall be applicable." I have been asking the builder on email regarding the dispute but he is not telling me anything. Thereafter i have received a letter from the arbitrator for further proceedings. I have a few questions in relation to the above mentioned context and i would like to have your kind advice on it. Q1) Can a arbitrator be appointed by the builder without any disputes raised from my side? Q2) Is it mandatory to appear in the arbitrator proceedings or we can send a letter to the arbitrator and the company saying that we are not aware of any disputes and thus the arbitration should be cancelled? Q3) Can we challenge the decision of arbitrator in Consumer forum because i have heard that the decisions given by such arbitrators are biased and favours the builders? Q4) Will my old case related to the cancellation of the old flat be impacted which is already in consumer forum? Q5) If there is any verdict of Supreme court/ Any other body in a similar case like me please suggest. Please suggest how should i move ahead in this regard. Many thanks in advance for your kind help on this. Regards