1. Choose Expert install while manual installation
2. Use WYSIWYG editor = No
3. Just check the language files for the supported languages exists. /lang/ & /lang/UTF-8/ it should be there with the downloaded zip.
4. We remove following code from .htaccess

php_value session.use_trans_sid 0
php_value register_globals off
5. Choose mysqli while manual install
6. PHP REQUIREMENT LINK : https://docs.s9y.org/docs/users/getting-started/fresh-installation.html
7. We have updated the PHP to 8.0 because since 2.4.0 script uses array_key_first() which requires min PHP 7.3. Since PHP 7.3 reached EOL vendor has suggested to keep min PHP as 8.0 (They shall update the docs soon on their website)
https://github.com/s9y/Serendipity/issues/794