The ansers, as far as I know them:
1) No, that is the only version of VAF. It does seem odd they don't have a more recent version.
2) v.6. The same version.
3) v.9 is current. I don't know when it was introduced, but it was relatively recent.
5) Have somebody with a more recent version open it for you. They can save it for you in a lower version, or create a GEDCOM file.