1. A method for a centrally policy controlled gaming machine that includes a game controller and memory storage to authorize execution of downloaded software, comprising the steps of: running in the gaming machine a version of Microsoft Windows operating system having Software Restriction Policy capability; setting the Software Restriction Policy to authorize execution of software code-signed with a certificate from a designated trusted party; providing a driver that is configured to take full control of the gaming machine and to carry out security verifications independently of the operating system of the gaming machine; causing the provided driver at a predetermined time or upon a request to take full control of the gaming machine, to disable all interrupts and to verify all or part of a content of the memory storage against a reference to verify that the Software Restriction Policy is operating on a trusted base; triggering an alert when the verification step fails, and causing the provided driver to relinquish control of the gaming machine.