Shouldnt the landlord have sorted the property out before letting it out?
Anyway my boiler is also a raven heat, and i also have a few of the problems you have.....condensation on windows
,they just tell ya to open your windows and have ya heating on to clear it up!!
... also used to have a cold house until my landlord installed loft insulation, maybe yours needs some or it may need topping up!, what i do know is that if any room is 50 C or below then its too cold, and your landlord should do something.