There is an error in the SQL record.

At the end of the SQL record you got :
[...] 'tep_cfg_select_option(array('true', 'false'),');

BUT

YOU MUST use
[...] 'tep_cfg_select_option(array('true', 'false'),');

Without this correction you have a "1" and [nothing] instead of a "true" or "false" choices.

Here the full packtage with this bug fix.
Download this.

All credits to authors,
Enjoy.

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