There is actually a neat workaround in Road Runner just for this. You use a label, with an EXEC command to fire any command you want. The button is transparent and will work on top of album art with no problem. I have one of these labels over the album art in my skin to change to the next and prev AVS styles.
Just change the NEXTAVS to VISU if you are wanting to turn the visualization on and off with it.Code:L,236,82,249,378,,,,,,"EXEC;NEXTAVS||=",