Check the demo project in the /img/system/ folder where the buttons are stored for example buttons. They have 2 states, normal and pressed, in the same image. The image is split 50% to separate both states.
Assuming you are using my spawn event plugin, store the last spawned event ID into a variable.
In Control Variables, set it to script:
Then use the variable code in the text message. For example, if you stored it in variable 9:
\pop[\v]This is a message appearing...
I don't know why running a common event would stop the OcRam_Layers plugin from animating. It doesn't sound like they should interfere with each other at all.
What is in the common event you are running?