No setbacks left and now being threatened.

Hi all I have a house in a 60x40 property in southern Bangalore. This house 3as built 18 years ago with appropriate setbacks. The design of the house is such that it resembles a Chinese temple. The ground floor being largest and successive floors using only 70 percent space as compared to the previous floor. A couple of years ago, the plot behind our house has been occupied and they have build 8 apartments in a 60x40 plot. Needless to say that they haven't followed the appropriate set backs which are mandated by the BBMP. Their wall is 2 feet from my compound instead of the normal 7 feet. Due to this we don't receive much light in our house. Also, due to the road being at an incline, our property is at a lower level than theirs. Hence their parking space is at the level of our dining area. Their servant's kids put their hands through the grill and start begging for food whenever we eat and we have on many occasions complied as well. But this is particularly embarrassing when we have guests. In view of the poor lighting and lack of privacy, we planned to put glass doors at the kitchen and dining area and to add privacy, we wanted to increase the height of the compound wall between their house and ours to 12 feet from the existing 4 feet. The neighbour has a problem with this since he says he won't get light. But the issue is that, had he followed the set backs necessary and left 7 feet as prescribed by BBMP, he would get all the light needed. Now he is threatening to stop our construction. What can be done?