(I saw your post there as well, that was mainly just for the rules and sign up, not really for people to openly talk about what they're doing)
I think it's fine. I can't really say, since I haven't ever done this before, or know exactly what they're expecting. But I've see/known people who did the cosplay contest as original design versions of characters.
That I can assume, the judges mainly look for workmanship and how well you did the outfit, and did you buy thing then change them or make it all by hand...etc.
The official people would be able to answer better than me, of course. But I think it should be fine. Kinky and I will have to do the same thing on some parts for Haku and Neru, so once you find out, let us know!