Thank you for your post.
When a carriage return is entered into a field, as you have discovered, this is stored as ASCII-11 (0B Hex); not the regular ASCII-13 (0D Hex). When you export this information, the ASCII-11 characrer is retained. This is needed for comma-delimited and tab-delimited text files, as the ASCII-13 character signifies the beginning of a new record.
The easiest solution would be to use a Text editor after the file is created and change the ASCII-11 characrer to ASCII-13. However, one customer wanted to do this all from within FileMaker Pro. In that case, a second Temporary table was set up where all the field and the first line of the text field in question was put into one field of one record in that table, subsequent lines put into separate records, and the last line and the remaining fields put into the last record. The user then exported the temporary table to a text file, as each record (and hence each line from the text field) is exported. I know it isn't the ideal solution, but it is a way to export the desired output from with FileMaker Pro.
Please let me know if you need additional clarification.