X5 + Word 2011 + Lion 10.7 (Mac)

Several months ago I purchased version X5 and have noticed that there is a quite significant lag for adding/removing references using endnote. It seems that this problem has gotten worse with time, but I am not sure. When I restart my computer and reopen endnote the problem is slightly better, but after a few minutes it is back to being very slow.

Any suggestions? 

Much appreciated. Thanks.

Hello, Macuser:

Quit and then reopen Word with a new, blank Word document. Is it also slow to insert into this document?