Two options:
The fjirst option is exactly as Steve mentioned. I'll just extend that to say that if you want to use Play and Pause symbols then instead of inserting Playing or Paused you can insert - for the Play symbol and = for the Pause symbol and then change each of those character's font to Crestron AV.
Based on your first thought of using an Advanced Button you have to change the mode states. Under Mode 0 there are options for Normal, Pressed and Selected.
Normal is what is seen if there is no feedback.
Pressed is shown when the button is pressed, provided you have "Show Local Feedback" checked.
Selected is shown when the Digital Join is High, so instead of using 162 for Pause feedback you would want the feedback wired to 169 on the touchpanel.
Each state is capable of having an individual icon assigned to it, so you can change each one based on how you implement the feedback. Each state can also have the button style changed, so on the Selected you would probably change that to the "Up" state of whichever button style you're using, that way when the state is selected it doesn't look like the button is pressed.
The one negative thing about this is if you use local button feedback for the button then the icon can potentially jitter. If the player isn't playing then you see the Play button. Press the button and the Pressed state is shown, which will show either the Play or Pause symbol, depending on your choice. If the player doesn't immediately change states to Playing then if you chose the Pause symbol for Pressed the user may see: "Play", "Pause", "Play", "Pause". This would correspond to the sequence of: Button Not Pressed, Press the Button, Release the Button, Player Plays. If you choose the Play symbol you might see similar jitter when pressing the Pause button. If the player doesn't immediately Pause then the user would see the Play icon when they press the button, which would change back to the Pause icon when released, which would then change to the Play icon after the button is released.
