Just to add to this (for info only) – I resolved my problem outside of this plugin. I use Gravity Forms so in order to enable subscription to mailing lists I created a checkbox option on the form with some conditional logic after the user clicks the submit button. This simply checks whether the checkbox next to a certain mailing list name is ticked and if so sends a subscribe email to the mailing list containing the email address which was entered by the user.
Whilst this isn’t completely ideal for all solutions (ie I don’t know how I can get it to add in their Display Name as well as email address) – it does mean I can get users to subscribe to lists and retain the email confirmation.
This plugin is still really good and I like it that it integrates so nicely with the profile page. If there were a simple front end widget to do what I’ve done independently, then I think that would be a great bonus.
Thanks,
Richard