Hi, Flea40 and all
The following link will provide you with all the information about the SlingPlayer Mobile application for the Windows 7 Mobile devices.
As stated in our web site, "New North American TV standards have expanded the demands placed on our software and hardware. We can update the Slingbox Software (also known as "firmware") in our older models and update SlingPlayer, but as time goes on, older hardware limits what a particular Slingbox can do.
As we develop Slingbox Software and SlingPlayer with new features for these new standards and platforms, these older Slingboxes may not necessarily be able to work with them. This also limits the Slingboxes that we can continue to provide software and support for."
I hope this information answers your questions.