Reading XML File with Stage File Action in OAICS, problem with Schema Option

Summary

Do I need to create new Schema or Select and existing Schema?

Content

Hi,

following on from a previous post (https://cloudcustomerconnect.oracle.com/posts/1c2636fd6c) I am having issues when trying to read entire file in my Stage File Action. The file is c-XML and during the config of the Stage File Action, Schema Options tab, I have the option to "specify the structure for the contents of the file" defaulted to Yes and greyed out. So I have to either create a new schema from CSV file, or select existing schema from file system.

As we have example XML files, I’ve tried to upload that, without success. I have the c XML dtd file,