The fact that something is free, doesn't mean it isn't copyrighted, when it was for a specific purpose, e.g. when run with the avast UI, namely Avast4.
You haven't said what your intentions are, so no one is likely to help (even if they have an old skin) if it is likely to infringe copyright.
Those who have just signed up to the forums and start asking things that aren't really related to Avast support related issues do have people worrying about the intention.
