Thanks for reporting the issue. I will look into why the button does not work on Safari.
The error is most likely due to a character set issue.
What character set is the file using, my guess is some "iso.." character set?
You need to convert the file to either plain text, or UTF-8, for UTF-8 see http://docs.moodle.org/24/en/Converting_files_to_UTF-8.
If you email the file to [email protected], I can take a look at what the issue is.