I tested out the other suggestions as well without any positive result.
So I got started to read all examples on setting up forms in AC and to test all possible ways to get the field to be working, and ended up with changing the form from attribute to element which gives me the correct rendering of the content.
Thanks for the help on ending up with a solution
Now the client has changed their mind and want a HTML fallback.
So ill need to get my head around building that one now..
First of all, because you need to keep xml="true" to get mData type, in case of your raw text exceeds the DB varchar size limitation (4000 or 8000 characters usually depending on the DB) so it is better to keep NTEXT /CLOB DB type to store the raw text as for html.
In your case, the memo field should contain raw text type.
Because XML management rule is to not take into account several spaces, line breaks etc. It is up to the XSLT engine to render it/display it with line break, indentation, etc, depending on the XSLT style sheet defined.
By the way, one suggestion: why don't you generate the text version when empty by using the nms:delivery.HtmlToText(htmlContent) method instead of putting "No text content inserted" string? Even if not ideally generated from html content, it is probably better than nothing no "No text content inserted", isn't it?