Transfer of room in pagdi system

I have a room in pagdi system in south mumbai, The Landlord gives rent receipt in name of my grandmother.My Grandmother had 2 son, one son (my father who died in july) use to stay in this room and another son (who died early in 2000) left the room long back before 1980 of 1990. I'm 1st sons daughter who lives in this room now Now the landlord brothers son in law n son's (whi don't stay over here) are not allowing us to us common toilet and said we need for our personal use or else we need to close all are room. They will build a toilet in our room by extending are bathroom which is inside our room. My question is 1. Can this room be tranfer to my name As when my father died i was here and i used to stay for atleast 7 or 8 months in a year and Im a widow. 2. Is BMC permission is required to build toilets by little extension of bathroom?? (The same will be built by landlord) 3. I would be treated as a tenant and possession holder. 4. Can landlord send me notice to vacant the room as i have agreed with landlord to build toilet and they will also give permission in writing but can they take action??