ENDNOTE X4, X5 AND X6 FREEZES IN WINDOWS 7 64 BITS

Hi, please someone help me! Every time I try to access endnote X4, X5 or X6 in my new version of windows 7 64 bits (HP Touchsmart TM2 64 bits processor) Endnote freezes e takes to much time to open the library. Even when I´m in the library I have to wait too much time to select a reference. When I open the reference I want then I have to wait again if I want to close it. Initially I solved this problem using the compatibility mode in Windows XP service pack 3 and then using my Administrator’s rights. And this worked very well untill two days ago when, I don´t know why, everything came again to the same problem. 

PS: I found that when I close the “preview panel” then I have easy access to the library again, but when I try to open the references I´m in trouble again.

Thank for your attention

lmb