Thanks for the "Else" tipp. Although according to the Manual Sub-Events: <font color=blue>https://www.scirra.com/manual/128/sub-events</font> should work my way too, therewith the color successfully changed on doubleclick...
But the text doesn't :( .
My understanding for the sub-event was, that it uses the same starting event, i.e. Nr.2 on the picture, and executes the sub-events all at once... or maybe in a row?! Anyway, the Text sub-event Nr.5 should work for both cases.