Sorry about the trouble. Not what we like to have for you, but to carefully transfer all the content for a better viewing experience, this is a temporarily side-effect. Again sorry about that.
The will video will be soon available again.
I guess what you need is an intro about GOZ.
Have a look here:
The manual states R14, but I guess it should be R11 and above.
(I have written to the Pixologic support and hope to clear that point soon.)
Please note that GOZ is not available for ZBrush-Core.
Either way. the comparison list shows what formats exist for a manual round trip.
The format OBJ is given to all, FBX for the full version, or STL.
My best wishes