I'm referring to a 1999 Stephens report by John Corcoran. As far as I can tell, the Microsoft agreement (still in effect for another 11 years unless it has been renegotiated) has to do with IPGs in Microsoft hardware and Microsoft operating systems. So, unless Microsoft is manufacturing Comcast's box or providing its operating system, I don't think any revenue will flow through Microsoft to Gemstar.
However, "Microsoft also agreed to pay Gemstar approximately 20%-30% of any IPG-related revenue from advertising and e-commerce over any platform." So, depending on Microsoft's deal with Comcast, maybe it will generate dollars for Gemstar.