Hi gorand2,
To see the error message you need to hover over the light bulb on a left ruler in the editor. I agree that it also should show when you hover over text. It is a bug on our side and I am going to add this to the list of changes in one of the upcoming releases.
To control the visibility of an in-editor context bar, please open Preferences -> CodeMix -> Editors -> Layout. There are several checkboxes that you can use to customize what should and what should not be visible.
Kind regards,
Wojciech Galanciak