GTW

You mention back boot space, are you meaning the area the roof folds into if so in that area both sides are drain holes to take away water from the roof, if they become blocked the water ends up in the area I think you talking about. The drain holes require unblocking.

Yes they are prone to leaks, my brother in law had one from new and after 12 months started to show signs of leaks. I have found various things on the tinternet as well. 1. The seals all around require to be treated will silicon spray to help keep them supple and not dry out, these are a known failure and the brother in law had them all replaced. 2. Top of windscreen in the seal of each corner there is a bung which over time the adhesive fails which means when it rains or you wash the car in tracks back and ends up in the car. 3. Poor seal of roof to side window which either is manipulation of seal to get a better fit or reset of door or inbound of glass, with the later requiring the door card to come off and part removel of vapour seal. 4. My water ingress was from a poor vapour seal in the door which allowed water into the car, so I had to take the interior out to dry it due to that much water, the only thing misding was fish there was that much. 5. And goes with out saying taking good care of the roof goes along way. At the end of the day its a rag top. Hope some of this helps, I have had mine 6 months now and I have a grin every time I take her out, yes I have had issues with water but hey she is 16 years old so would expect something.