InfoPath Dev

I found that THIS post works.  The main difference is the use of preceding-sibling and following-sibling instead of xdXDocument:get-DOM() in the filter. Only draw back is you have to make two filter rules instead of one.

 Attached is my attempt at the example posted here.

 So the filter should be on the combo list in Main and not on the actual data source?   Screen cap of the drop down filter config. http://1drv.ms/1l4nUlY 

 I am new to InfoPath and SharePoint 2013 but I am picking things up quickly and really enjoy the flexibility of the platform. I am however stuck trying to get a Shrinking list filter to work on my dropdown list in a repeating table. I am trying to follow this example here but just can't get it to work. My data source ...