You can do math with Datalinq Keys by encapsulating your statement in <> brackets. So you'd enter <%ROW1%+1> for your ROW2 Datalinq Key, <%ROW1+2> for ROW2 Datalinq Key, etc. You can also just have a single Datalinq Key that's your ROW1, then do that same math in the Datalinq settings for the specific text objects.
If you add the XPression device in Dashboard as RossTalkEX, there is a SetDataLinq command available. 
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Jeff Mayer
Ross Video
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