On the Mac version, you will find the Autoloop toggle as the 2nd icon at the bottom of the Marks List. Show the marks list by clicking the far left icon or choose it from the View menu. You can then also toggle the Auto loop from the Marks menu.
Thanks, that makes sense and I have it working now. My use for learning harmonica blues licks results in setting A & B points around licks along with slowdown a great use of Anytune.