Trying to get my head around your response. So you are saying that if you performed a ceremony within the capacity as pastor, with the couple knowing there is no license and you cannot legally solemnize them, you are in trouble.
It seems to me that if the couple knows that fact, and you do not sign the license, then there should not be a problem. i would have them sign a paper verifying that they know what you do has no legal standing. Beyond that, with you not representing yourself as an agent of the state, I see no problem.
