Dear Sir,
My answers are as follows:
1. Is it legal to use a room which was storage room to now storage waste if it is not in a sanctioned plan?
Ans: It is illegal since its situation is not shown in the sanctioned plan.
2. If the association is bullying their way, what are the legal options available to us?
Ans: You may immediately approach a Civil Court and get a stay order on such construction of storage room.