Navision Deployment (client) through Group Policy

We deploy all software through grou policy but we do not use SMS server. I see that the client includes the appropriate files for deployment through SMS but I cannot build an installer package (MSI package) using Wininstall as usual. I lack all technical documentation as we are just in the process of the deployment. Can someone please let me know if there are any command line switches that I can use with the original installer to allow for a predefined install (answer file?) or silent install? It is a bad time as it is so near the holidays and everyone at our distributors support line is on holidays. Please Help.