I don't think anyone has found any beta for any of the Sly games, but there is a couple of demos with beta content(E3, Jampack, others, etc.) for the first game. You can easily google it if you are interested. Who knows? Maybe one day a beta will pop up (I still have hope for this). Also, during the Mz. Ruby boss fight I think Sly says:"Dig that voodoo!" or "Zig zag voodoo" with each button representing one of those words or a syllable of the words.