It would help make it clearer if the boom was in the centre and the leading edge was fully inflated.  The boom has to work with the 4m and the 7m, and I expect that the 7m is a larger diameter leading edge than the 4m?

I would expect Duotone to have designed the 4m to 7m wings to match that boom, but the other problem they have is that the 5m and 4m also have to match the shorter boom for the 3.3m and 2.6m wings.