Rolling 24 month graph

Hello Guys,
It's first post ever on any forum. I am looking for assistence

1. The assistance given in following thread is great but it is not allowing me to define source in column (see attached file please in this thread)
http://www.excelforum.com/excel-prog...ith-dates.html

2. I want my current graph 24 month rolling but my graph data will linked with another file, so the values appears in the graph will be 0 for further month of the year. which On the graph is quite distracting for user. For example the user wants oct 2006 to oct 2008, as the value linked with another sheet, so the value appears on data table will be 0, the graph atutomatically pick cell values, so can this not appears on graph (see attached file please)

regards
shahid