X2 sort of. With everything clean take a careful look to see where the leak is; you might even want to add some UV dye to the tranny fluid. If it's just the connections there are likely solutions.
Otherwise yeh install an aftermarket tranny cooler just behind the grill, there are several suggested installs on the forum or check
http://liberty.eurekaboy.com/transcooler.htm . Not a CRD specific issue; most all vehicles combine the tranny cooler with either the radiator or AC evaporator; stuped bean counter solution. If the tranny cooler portion fails the best solution is shift over to an aftermarket; don't try to repair/replace that combo unit (just makes the stealer happy).
Now if you are an old fart like me that remembers real copper radiators and local radiator shops; in the bad old days that leak could be fixed for next to nothing but today we are stuck with the wonders of plastic and aluminium.