As of QIE version 3.0.44, you can quote and unquote text within your script from the Edit menu of the text editor.
For example, open a custom mapping function and select the unquoted text like this:

Then go to the Edit > Quote Commands > Quote Selection from the menu bar, like this:

You can reverse this process if you want to get the unquoted string by selecting the quoted SQL query, like this:

Then go to the Edit > Quote Commands > Unquote Selection from the menu bar, like this:

If it is unable to perform the quote operation, or you haven't selected any text, you will receive a message like this:
