I used both versions 7.0 & 7.1 to communicate to devices on the IIC bus. I did not have any problems.
Can you walk us through the problem that you are having?
What are you using to interface to the bus?
What worked (how) using LV6?
What to your knowledge changed when you upgraded to LV7? What drivers did you have to install in LV6, for instance..
Sorry to ask so many questions, but I need more info to provide an accurate solution.
-JLV-