[TYPO3] Troubles with Front-end User List (gsi_feuser_list)

[Robert Markula]

Hey folks,
There are many reports that gsi_feuser_list does not work and produces 
errors in the FE. I've yet to find a working bugfix.

The errors are:
**********************************************************************
Warning: mysql_fetch_row(): supplied argument is not a valid MySQL 
result resource in 
/path/typo3conf/ext/gsi_feuser_list/pi1/class.tx_gsifeuserlist_pi1.php 
on line 91

Warning: mysql_fetch_assoc(): supplied argument is not a valid MySQL 
result resource in 
/path/typo3conf/ext/gsi_feuser_list/pi1/class.tx_gsifeuserlist_pi1.php 
on line 148

Warning: Cannot modify header information - headers already sent by 
(output started at 
/path/typo3conf/ext/gsi_feuser_list/pi1/class.tx_gsifeuserlist_pi1.php:91) 
in /path/typo3_src-4.1.1/typo3/sysext/cms/tslib/class.tslib_fe.php on 
line 2898
**********************************************************************

Did anybody ever find a solution yet?
Typo3 4.1.1 and gsi_feuser_list 0.6.5.

Cheers,
Ro