Please, I need help with some items.

Could you please, help me with the following items?

a) They are prohibited to watch violent films or they are prohibited watching violent films. (?),

b) Can we refer to a long improvement on our home as a long reform ? And does the word "renovation" can also be used in this context ?,

c) When the improvements on the house finished, the family set up the furniture of the rooms. (Is it correct to use set up here?)

d) Referring to the word 'couple' we have to use the pronouns it/its , don't we ? For example: The couple next door decided to hire a maid to take care of its house. Now it (= the couple) has more time to solve its daily problems, pay its bills and take care of its children itself.

Thanks a lot,

Muriel