1. Avastar is guaranteed to work with the most recent Blender release.
  2. Avastar might work with older blender releases from last year, but no guarantee.
  3. Never unzip the download file. Give it to Blender as we gave it to you.
  4. Read the documentation!

If you refuse to read the documentation, then Avastar is not for you. In that case we happily refund your purchase. Nothing wrong with that.