Hello SK,
As far as I can tell from the databases, all the 2003 2.2Di 112bhp Xtrails are rated by the manufacture to be able to pull a braked trailer with an MTPLM of 2000Kg, So your choice of caravan is well within the cars mechanical capabilty.
Good towing as about getting a wide range of things right, not just weight ratios, so you must also be aware of nose load, good distibution of weight within both the car and the caravan, ensuring all the mechanical parts are in good order, adn in my veiw the higgest consideration is how to tow sensibly.
Bearing in mind that caravans are physically large trailers, and they present a number of towing issues which means it is always wise to keep the caravan as practicaly light weight as possible.
The the quoted kerbweights for the 2.2Di models seem to be in the region of 1615Kg which based on your quoted figures gives a notional ratio of about 89%.
So far I see nothing in the figures that worries me.
I am sure that other contributors who have similar outfits will be along soon to add a bit more detail.