I took the liberty of converting your ticket into a forum question, since it did not contain any sensitive information, and can benefit others.
The "Text as a single cell" format only exists as a source. We don't provide it as an output, since it's of very limited use; it would only work for a 1x1 table of data.
However if you do have a 1x1 table of data (a single cell) and you wish to export the single cell's content to a txt file, you can use the Delimited output option as follows:
For example, here is a File input block linked to a File output block, recreating the same file contents: