Hey Pablo, there is an adaptor for the crusader, it is a thin sheet of steel with the same shape as the crusader cut out and the edges bent over to give it rigidity. It stows over the hexi cooker perfectly and means you can put your cooker up without having to resort to the angled set up of the legs. They come as standard these days with the cooker and the hexi fuel all wrapped up in that brown waterproof paper.
Whe the crusader sits in the adaptor, the bottom of the cup pokes through and the cup is suspended at its mid point by virtue of the fact that the top part is wider. The cup therefore sits close to the hexi and gets very well heated.
If you want one of them, I'll have a look when I get back sausage side and send you one across, it will make your life so much easier if you use hexi cookers a lot.