Access JSGrid in Project Schedule

I have run the SDK demo [Walkthrough: Customizing the PWA Ribbon and] Accessing the JS Grid.  This works only in the Project Center page and does not work in a schedule page.  From the narrative, I should be able to get grid info from any PJ page that has a JSGrid.  What do I have to change in the code that allows me to access a schedule page?  I suspect that the "ProjectCenterMain" name in the initial OnLoad...call is what has to be changed.  If so...to what?  and ... where does one come to know the names of all such things within the model?  Thanks.