I love Pie Register and have had no problems with it so far, it works a treat on a standard user registration (I am using the Email verification method)
However, I also use One-all’s Social Login plugin so people can login/register with Facebook. I would like to hack their plugin to call the new user notification functions in Pie Register, but cannot quite work out which functions are used by Pie register to perfomr its magic!
PR invoke “pie_save_registration()” function at the time of
registration,. this function not only sends email to users and admin but
also save registration into database. I dont think you can use this
function with other plugin however you can extract the email part link
variables to make it working.