We have been making modification to Jevent and DT register for event registration in Japanese site of Joomla.
We made one custom programing calls Hayawari (early event registration discount) until prior 20days before the events.
We made almost done.
there two different user methods which are member and non member
there are two different payment methods which are Pay later and Paypal.
Problem is discount shown in front but not reflect to confirmation email to customer and not reflect to dt register admin event registration manager.
I think need to fix code of script check out script of this and mysql.
More detail need to chat, SKYPE or YM required
Expert Joomla programmer ONLY