Basically, I am trying to do a mouseover, but it’s not working. When the player moves the mouse cursor over the Trophy1 object, I want the Achievement1 object (which is text) to appear. When the player does not have the mouse cursor over Trophy1, then Achievement1 should be hidden. Thank you for your help!
I think you are creating a lot (really a lot 
) of Achievement1. Your game usually runs at 60fps: in each frame, if the cursor is over Trophy1, you are creating an object Achievement1, and I can see you delete it, so if you keep the mouse over Trophy1 for 5 seconds, you get 300 objects!
You should:
-Add a “Trigger once” condition in event 43, so only one Achievement1 is created each time the cursor is over Trophy1, and delete the Achievement1 when the cursor is not over Trophy. or
-Create an Achievement1 when Trophy1 is created and hide it, then, when the cursor is/is not over Trophy1, unhide/hide Achievement1.
Let me know if this work 
Thank you, Lizard-13. After thinking about what you wrote, I decided to simplify the achievements by using text that is shown at all times, thus I eliminated the need for a mouse cursor hover. I appreciate your continued help.