I have to agree with Chronos -- the change in color scheme doesn't really help with the revamp, and the functions are a bit hard to catch, but the quality of the MOC is great. I'll give you an eight -- if the colors were right I might have given you a ten, which is a rare move for me. :)
Brilliant job, but the bulk just kinda ruins it for me, as I always imagined the Visorak being spindly like an actual spider, and the gunmetal just doesn't work on this, seeing as the original was mainly white.
I have no idea what the category was, but man, that is a nice MOC, especially the limbs. I do think you should've gone with a little more color, or made it into an Oohnarak, but it's neat regardless - the white carapace contrasts interestingly.