Of course the the display text briefly action doesn't cause a button to be pressed. I suppose I can see how you might have read that into what I wrote. Kindly re-read (I'll embolden the points that should have emphasis)
...the display text action.. prompts the user to highlight a portion of the text
"...thus pressing down on the L mouse button," meaning, the user responds to the prompt and presses down on the L mouse button. I originally used the tried and true 'Prompt For User Input' action but decided (since the was going to be used for batch creating), I wanted to simplify and streamline. And so, I placed the (highlight) prompt in a Display Text action and then placed a Pause Until action after it.
It eventually turned out well. The macroworks. As soon as the user (responds to the prompt) and highlights text, using the L mouse button, the next action is triggered. My original point is simple enough. The macro had problems when I inserted a Pause action between the prompt and Pause Until for the reasons explained above. I just wanted to point that out. That's all.