MINI says max towing on a Clubman is 1500# with ~100# tongue weight (from the web).
If you keep from overloading with too much junk in the camper, you should be fine.
My 74
boler weights in at 950 lbs, including all our food, clothing,
propane tank and such. Tongue weight is usually 50-70 lbs (I usually have to be carful to load our duffel bags of cloths on the front bench and our two coolers on the floor, at the front of the camper, to increase the tongue weight, otherwise she bounces on the hitch). Avoid just tossing everything into the back of the camper onto the bed!