Large Endnote X4 library networked -- very slow -- solutions?

I maintain a 73 GB (and growing) library with ~18,000 citations and all have PDF attachments. Is there anyway I can alter the functions of the software in order to speed up opening and editing the library? I know the network and size slow things down but would love to be able to get rid of PDF indexing function or something else that would speed things up. About 40 users have access. Thanks for any help.