Sometimes when I try to configure a Log History Message, I get a strange error message which makes me abort and find another way like the "Common" Section of another control to display my variable.
The message is "You Must Display an Action Title". The Action Button is greyed out at that time.
Later if I try it again, it works.
Don't exactly know what you mean. I just put a reference variable to display. Sometimes I have some text and the a variable. Sometimes just text. I've seen this a number of times.
I have the same version as you and am encountering the same issues. It's not just with the Log History action though. I've had it happen with a number of actions. Usually I can close the action, then reopen it and it will work fine. Really annoying though when it happens. Maybe this is a bug with this version. Have you sent anything to Nintex support?