When a Collaboration Link is created, you can visualize it in the
Collaboration Links tab. They will be grouped by Collaboration Link type and they will include an icon and a title.
If you are entering Windchill and you have not started a session with the CLM Application yet, you won't be able to see the actual
icon nor the small preview of the remote artifact. The small preview is a shortened view of the artifact (just the most important properties are included) that is displayed when you
pass the mouse over the artifact link for a second  (and you have started a session with the CLM Application). What you get hovering the mouse on the artifact
link without a session is a way to start it: you will see the message:
Log-in to see the preview content. In this scenario, you only need to click on the
link embedded in the message to start the authentication/authorization process and get the small preview along with the actual icon and title . If, on the other hand,
the message that you get is
No preview available., means that there is no friend application registered for this link and therefore, there is no way to get a small preview,
please contact an administrator to see whether is possible to register such a friend application and get small previews. Finally, if don't get a message at all, means something else is wrong,
please contact an administrator to inform her/him of the problem.
There are no differences between having a GC compatibility configured or not in your Windchill product regarding above functionality. It will behave the same either you are using GC's or not, you just need to remember that in case you are using a GC, the small preview will correspond to the versioned artifact corresponding with the GC being used.