I find after the "Endnote X5 + Office 2011" cannot work well together on Mountain lion and retina display. Because the input of words in Word file become lag! After removing the "add-in" of Endnote from Word file, the input of Word become smooth again. There is no problem for Excel and Powerpoint, because there is no "add-in" of Endnote in them. Does anybody have seen the same problem? It is really annoying! I have tried the newest Endnote X6. I have to say X6 is a stupid version. Because: firstly, it is very lag under Mountain lion system, very lag! Secondly, the UI of X6 is stupid and I cannot understand why it is so complex and useless. Thirdly, the PDF preview cannot be turn off! Retina Macbook Pro | 2.3G | 16G RAM | 512 SSD, Mountain Lion 2.8.2.