As well as the issues with XP which several people have also reported, there are quite a few other issues with ADE 2.0.
Unless you really need one of the new features of 2.0, I suggest you just continue with 1.7.2.
Maybe when 2.1 comes out they'll have killed some of the bugs.
Thanks for the update 1.7.2 is just fine. I went to 2.0 because it was down loaded automatic when I was downloading an ebook from the library