Great question. First, let me answer your first question on the locations Project searches for Global.MPT 1. The current folder 2. The user’s profile folder 3. The user’s profile language folder 4. The folder where the Winproj.exe file is located 5. The Winproj.exe language folder Source: More information section from http://support.microsoft.com/kb/163093
On your second question on sharing Global.MPT use the following steps 1. Copy Global.MPT to shared folder (like \\myshare\project) 2. Ask each user, to create a short-cut of Project on their desktop 3. Edit the short cut and set the Start In folder to be shared folder 4. Now, the user launches Project using this short cut, Project checks the Start In folder rather than current folder.