Software Deployment

I am trying to deploy a product called Inservice (ICAD_NET) from Intergraph. They have supplied an MSI with their install files. First I just launched the MSI by itself to see what would happen and I got an error saying "This installation can not be run by directly launching the MSI package; you must run setup.exe." I looked in the forums and found this same message with other applications. I followed their advice and tried the following to the MSI:

Deleted OnCheckSilentInstall from Custom Actions
Added a Property called ISSETUPDRIVEN with a value equal to 1
Also ran setup.exe and looked in temp and saw that it extracts ISScript.MSI. Then ran ISScript.MSI manually

After doing those three things I tried running the main MSI again and get a different message this time. I get a System File message saying "One or more system files are currently in use and a re-boot will be required for the Setup program to complete the installation."

I've re-booted and continue to receive this message everytime I run the MSI. I see nothing in log files or in Event Viewer that gives any clue about what file is in use (if any). I am running this on Windows 2000 SP4. Any help or ideas would be greatly appreciated.