Hi AAron,
The Multi User tool works primarily like using Xrefs in AutoCAD. You can share drawings and models using the various check in and check out commands and tools located on the Extended Modeling tab MultiUser panel . Here is a link that will explain how the tool is used. See link below.
http://www.graitec.com/en/FAQ_view.asp?FAQID=701&Language=EN&Name=How+is+the+Multi%2DUser+Function+used%3F
I hope this helps.