In their PDF they just saying
Precondition The Signal Editor is open.
Procedure 1. Click on the name of the input or output in the right-hand column. The name can now be edited.
2. Enter the desired name and confirm with the Enter key.
The name must be unambiguous within the current view of the Signal Editor.
The changed name is displayed in the I/O Mapping window
But in my case, it's all gray and cannot be changed (mouse click doesn't do anything other than make the Signal Editor refresh screen)
Or the KR-C4 cab has to be connected to the Fieldbus and running? If so, I'm using the KLI for WorkVisual connection now, and I had to use KLI for Fieldbus too.
What should I do?