The Velbon PH-368 head is all plastic and load rated to carry only 10 pounds (4.5 kg) according to
www.adorama.com/VNPH368.html
It is not a "fluid head" but "fluid-like". BIG difference. Reality vs marketing term. If you want "smooth" then you need a true fluid head. I hope the head is on the ProDVC50's camera platform - and not the support for the crane and camera - but just in case the jib is mounted to the Velbon head...