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That's great! Just what I needed.

For others who find this, it's SecurityPanel.UserDisplayNameVisible that needs to be set to true

I suppose this would require an extension to the security page, adding a full name option to users as well.

I think you can push app.config changes to the client by issuing a reinstall. Select the computer (or multiple computers), right click, Reinstall. It takes all of 5 seconds to reinstall and is invisible to the user.

You can also push this command "rundll32 dfshim CleanOnlineAppCache" via your RMM or the SC Commands tab to get a fresh app.config

You can change this in 5.6 already. In Admin > Appearances > Client Resources > UnderControlBannerTextFormat

I have mine changed to: "Your computer is being controlled by Company Name Remote Support: {0}"

Extra bonus points for detecting and clicking OK on a logon banner ( before entering credentials