s2Member's redirection after login is managed from WP Admin -> s2Member -> General Options -> Login Welcome Page -> Special Redirection URL. You seem to have checked that already. s2Member will not override a redirect_to field in the login form, that's the intended behaviour.
That redirection may be introduced by other plugins or the theme you're using. Try going to the default theme Twenty Ten and see if the redirection is still there. If it wasn't the theme, then start deactivating the other plugins one by one, checking the redirection after each, and see what causes it to change.
Once you located the source of the redirection, it'll be easier for you to handle it. You can also try adding this to the login page's URL: wp-login.php?redirect_to=/uri-to/the-page-you-want and see if that overrides the other redirection.
I hope that helps. Statistics: Posted by Cristián Lávaque — April 15th, 2011, 11:34 am
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