if I change line 135 of install/include/makedata.php from
$newbid = $dbm->insert('newblocks', ' VALUES (0, 1, ' . $func_num . ", '" . addslashes($options) . "', '" . addslashes($newblock['name']) . "', '" . addslashes($newblock['name']) . "', '', 0, 0, " . $visible . ", 'S', 'H', 1, 'system', '" . addslashes($newblock['file']) . "', '" . addslashes($newblock['show_func']) . "', '" . addslashes($edit_func) . "', '" . addslashes($newblock['template']) . "', 0, " . $time . ')');
into
$newbid = $dbm->insert('newblocks', ' VALUES (0, 1, ' . $func_num . ", '" . addslashes($options) . "', '" . utf8_decode(addslashes($newblock['name'])) . "', '" . utf8_decode(addslashes($newblock['name'])) . "', '', 0, 0, " . $visible . ", 'S', 'H', 1, 'system', '" . addslashes($newblock['file']) . "', '" . addslashes($newblock['show_func']) . "', '" . addslashes($edit_func) . "', '" . addslashes($newblock['template']) . "', 0, " . $time . ')');
it works again