This does not work.
I have poured through these forums, opened a service ticket, and chatted online with a service tech.
For shared groups in Endnote online and Endnote X8 right now:
(1) Shared groups cannot be synced between Endnote online and Endnote X8. You can only see a shared group online.
(2) There is a “bug” such that you can’t move references from shared groups into any other group.
(3) If you have a large enough shared group, you can’t export them because it will cause a gateway timeout.
(4) You can’t select or create a subgroup of references to export from a large shared group because of the “bug” and lack of this functionality inherent in Endnote online.
(5) Even with the plugin and Endnote online, you can’t see references from a shared group in CWYW in Word.
Basically, if you have a big shared group, you get to look at it online. You can’t move, download, export, import, or sync these references to anything.
Shared groups are completely useless right now in Endnote.