Hi,
Yes, this is sort of “by design” because these fields are not part of the fields available to use in a form. I guess I could make it appear in the field picker somehow, but you might be able to fix it in your form like this.
Start by adding a HTML section in the tab with the Unique ID “CreatedBy”.Then add this to the Custom JS:
(function addCreatedByToTab(){
var b = [];
b.push("<tr>");
b.push("<td class='ms-formlabel'>");
b.push("<span class='ms-h3 ms-standardheader'>Created by</span>");
b.push("</td>");
b.push("<td class='ms-formbody'>");
b.push(spjs.dffs.beforeProperties.Author[0]);
b.push("</td>");
b.push("</tr>");
jQuery("#dffsHTML_CreatedBy").replaceWith(b.join(""));
})();
Alexander