That seems to get me pretty close, I understand what you say about using max to determine the current max in the row.
I have included a section of my grid for clarification.
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I need the displayLine fields to be sequentially numbered from top to bottom. (1,2,3,4,etc)
right now the problem I am having ins correctly configuring the where clause in update field in table action. If you can shed some light there I would greatly appreciate it