Question: how to open zpr file in zbrush?
Answer: Open. The File Open button will open an previously saved Project (ZPR format). ... 
SaveAs. The Save As button will save everything that is in the document into a Project. ... 
Revert. The Revert button restores the current Project to its condition when it was last saved. ... 
UndoHistory. ... 
Lightbox>Projects. ... 
Project Notes. ... 
Edit. ... 
Open.