Converting from 2.5

I'm playing with the new 3.0.7 release by using the sequence conversion feature to go from VIxen 2.5 to 3.0.7. I'm sure there's a reason but I don't know if it is significant for me to know. When I do the mapping for the conversion I notice that the V2 channel and the V2 output are different by 1. The channel starts at 1 and the output starts on zero (0).

Is this something that I need to know about or be prepared to compensate for someplace else.... I'm guessing that column is there for a reason......and probably should be telling me something......?

THanks
SC