Each process can have multiple versions. The Working Version of a process is the only version where modelers can make changes.
The Working Version is typically not visible for normal users.
It is considered a bad practice to mark the Working Version as the Valid Version.
For Reference Models the Working Version has to be the Valid Version!
In Stages V6.x and older versions, the Working Version was known as the Working Revision. This has been changed for consistency reasons, the behavior remained unchanged.