FAQ: I created a new UCS from the ViewCube UCS menu. Why isn't it displayed in the list?
When you create a new UCS from the ViewCube UCS menu, it's created as an unnamed UCS. For it to be displayed in the ViewCube UCS menu, it must be a named UCS.
To Name a New UCS
In the drawing area, right-click the UCS icon and choose Named UCS Save.
Enter a Name for the UCS.
The named UCS is available for selection from the ViewCube UCS menu.