Here are some basic "getting started" instructions on how to modify the code to create a totally custom promotion in Version 4.4*.

1. Database - Add a new entry into the ZNodeDiscountType table for your promotion. Take note of the DiscountTypeID.
2. Code Changes - In Libraries/ZNode.Libraries.ECommerce.Buisness/ZNodePromotions.cs search for "DiscountTypeID". This will show you all the places in the code where we are doing something specific based on the DiscountTypeID in the database. Generally you can just add a new "if" statement to handle your particular case where appropriate.

*These instructions are created just by browsing the code and have not been tested. Be sure to back up your database and source files before making changes.