Hi,
I tried to project all the skin mesh I made by re-topping on the model but nothing happen by pressing project all. I s there anything else I should do in between that I have missed probably?
Have you actually skinned the ZSpheres yet, or are you still working in the preview mode? If you haven’t skinned them yet you would simply turn on Tool>Projection>Projection before activating the preview. This tells ZBrush to calculate with projection.
If you have already skinned the ZSpheres then you would append the new polymesh to your original before you use Project All.
In other words, Project All only functions when the Tool>Projection menu is not available.