OK, so I see that if I remove the Status 'Open' and recreate it, I have the "Update Problem" (I accidentally referred to this as "Update Action" above) in "Optional Action Instances". However, when I re-add the "Open Status" with the right action, I get this error.
"Error saving current process: Attempt to remove status Open that is in use from a lifecycle. You cannot remove a status from a lifecycle if there are lifecycle objects that are associated with the same status in the same lifecycle."
Ignore I understand the issue better now and will create a new thread.