I just recently had a conversation with one of our Services guys who was trying to get Bentley Navigator to install silently. We had some trouble with it as it appears that the old way of doing it has changed a bit. We were able to get it to work by using the same process that is described on the Technote - Installing MicroStation V8i Silently. I wanted to let anyone else out there know how to get this working. To run a general silent install for it, the command should look something like this -
msiexec /l*vx log.log /i Navigator.msi /qn+ APPLICATIONFOLDER="c:\Bentley Navigator" PACKAGE_HOMEROOT="c:\Navigator WorkSpace"
This will place install in the Bentley Navigator folder directly under the C drive as well as the workspace folder under the Navigator WorkSpace folder.