Is the database you are installing to a non-English MySQL installation? If this is true, open the sqlParser.class.php file in the Install folder and replace these lines, near the bottom of the file:
// Ignore duplicate and drop errors - Raymond
if ($this->ignoreDuplicateErrors){
if (eregi('^duplicate key', mysql_error()) || (eregi('^alter', $sql_do) && eregi('^duplicate', mysql_error()))) continue;
if (eregi('^can\'t drop', mysql_error()) || (eregi('^alter', $sql_do) && eregi('^can\'t drop', mysql_error()))) continue;
}
// End Ignore duplicate
with these:
// Ignore duplicate and drop errors - Raymond
if ($this->ignoreDuplicateErrors){
if (mysql_errno() == 1060 || mysql_errno() == 1061 || mysql_errno() == 1091) continue;
}
// End Ignore duplicate
You will need to empty the database and start over. This "fix" has been included in the next (0.9.1) release.