The healing amount can be modified in the Status_Data, not directly in the Skill. You have to copy the status REGENERATION and create a new status from it, change its name and healing value (else it will impact the vanilla skills), and attribute this new status to your skill in place of REGENERATION. After that you have to save and restart the editor in order for the change to take effect.
Last edited by Volsungh; 02/10/17 08:08 AM.