I want to send confirmation mail to participants for open-access survey,
from "survey administrator email address", not from "site admin email".

I got 2 ideas by Google

1. With LimeSurvey default confirmation system,
   It doesn't work for open-access survey.

2. With QuestionID "Mail" and then "{Mail}" into "Send X admin notification email to",
   It works but the mail sent from "site admin email".

Both of them don't satisfy my requirement.

Solution 1 - I recommend.
Put "Email To" selector on "Confirmation" tab in "Edit email templates" screen,
with options "Participants only"(for closed survey) or questions to get response value for email address.

Solution 2 - I think this solution is twisted.
Put "Sender" selectors on "... admin notification" tab,
with options "site admin email" or "survey admin email" or questions.

Please, think about.
Thank you.