This kind of question has come up a couple of other times on here.
Havok Cloth is not available through tryHavok. We are trying to keep the forums in kind of the realm of Havok Physics and Animation. If you are interested in Cloth for a commercial product, then it might be best to look at doing a purchase inquiry from the Havok website.
That's about the best I can tell you.
Thanks for your interest in Havok,Sean