Hi. Okay, it looks like pstotext is not successfully executing from exec($command,$result,$retval); in the robot_functions.php file. From shell type
locate pstotext to check the path. If /usr/local/bin/pstotext is the correct path and the output goes to STDOUT, the configuration you posted looks correct. Right after exec($command,$result,$retval); try adding the following and then reindex the avare2.html:
PHP Code:
echo $command . "<br>"; // try running this from shell in admin dir
print_r($result); // holds the output sent to STDOUT
echo "<br>" . $retval; // is zero if command succeeded