I am starting Word as follows:

• cd /d C:\Program Files\Microsoft Office\Office12
• winword /z"C:\templates_folder\template.dotm" /w /q

Switches:

• /z : Start with the specified template (there is also a /t switch that does the same thing except that it does not invoke the Document_New macro)
• /w : Start a new Windows process even if Word is already running
• /q : Suppress the startup splash screen