You may have already found a solution for this, but in case you haven't...
I
was having problems trying to get conditional formating for other
elements (a check box) to recognize the multiple lines of a repeating
table. The solution was the reference to the table. If you
use the InfoPath interface the coding will only refer to the first
line. You have to manually go into the file and change the
reference, or use the "expression" function to dig below the first
line. The key... brackets!
Here's an example:
I
wanted a check box to be selected if the value for a drop-down in the
repeating table was "1". When I set the conditions using the
InfoPath interface it came out like this:
my:group1/my:Observations/my:Item (starts-with(my:Item, "1."))
That worked for only the first line of the table. The solution:
my:group1/my:Observations [ (starts-with(my:Item, "1.")) ]
You can modify this by using the "expression" option and typing in the code, or you can change the code directly.
My hunch is you have the same issue. I'm a newbie at this, so I may be totally wrong.