Does anyone have a comprehensive link or file to explain how to use plug-ins. Im really new to WM and would like to learn how to incorporate more plug-ins to my today screen.

I guess my biggest question, is how do I know whether or not an application can be used as a plug-in, and then what do I need to do to get SPB Mobile Shell, or other programs to recognize it?

Any info on this subject would be greatly appreciated.