Umm, I mistake pointed. CSV output by receipt.php sorry.
So, represent questions.

What charset recieved CSV file from eguide module?
Is that file charset UTF-8 or NOT?

If that is UTF-8, check your reading tool for CSV.
Another charset has come, You need check your PHP setting.
You can check put "info.php" file and view by web browser.
<?php phpinfo(); ?>

Checking which to use, "mbstring" or "iconv".
And check converting condition if you can understand program.
(receipt.php line 140-)
--
Nobuhiro YASUTOMI (MySite Users Webmaster)