Ok, I have spent days on this now. I am currently working with support as well. I even reached out to are account rep because if this is not possible, I cannot use the software. I have found solutions for Nintex on prem, but that does me no good. I need a way for files attached to the list form to be viewed on the task form. Like an invoice. This seems like it would be a common requirement. What I've done so far:
I can grab the files using a web request from the list form. This gives them to me in xml format. Now I have not been able to parse the xml yet, but I can figure that out. But once I have the files in a collection, how do you display that collection on a task form? I understand I can do a for each in the workflow and all kinds of actions on a collection, but you can't do those things inside a task form.
So I'm saying this is impossible using office365 version. Am I right? I need to make a decision here on how to move forward.
Any help would be so appreciated even to get closure if it's not possible.