Boat on the bicycle carrier for the trailer coupling

Hello, I have a bicycle carrier for two bikes. Now I want to buy a GFK boat. But the boat does not fit into the car. The boat weighs about 45 kg. That is much less than the support load for the trailer coupling. The car is about 2m wide and the boat is about 2.45m long. I would have such a supernatant of about 20 cm. So from the technical data it should fit. Now to the question: Does something speak against that that I fasten the little boat on it? would not know that the road traffic regulations or ABE make any differences between loads. Unless any criterion is exceeded…