You may want to try this as it would appear that the HyperNURBSs is putting the arrow structure off a bit.
– Select polygon object from the ‘objects’ menu
– In the plan view (F2) – create a number of points that will be the edges of the polygon(s) that will make up your arrow or ribbon
– Bridge the points to form the edges of the poly. Some triangulation will occur but don’t worry about it
– Once you have created your ribbon / arrow go upto the ‘functions’ menu and select the ‘subdivide’ option. Put ‘6’ in the number box & make sure the HN box is UNCHECKED. This will now make your ribbon into a lot more polys so it will move more fluidly (or should that be ‘ribbon-ly’!) You can continue to subdivide the arrow but the more poly’s = more rendering time. I tried it just by doing the 6 subdivisions and it worked alright.
I can email you a .c4d demo file of what mine came out like if you want
Hope this helps.
Cheers,
Colin