The absolute minimum requirements for Kusaba X are:
Use MySQLi
Does your server not meet the requirements for neither MySQL nor PostgreSQL, or do you run a small server and don't wish to install either? Use SQLite. It requires no database software to be installed, only PHP and a webserver.
If this is the first time you've ever heard of PostgreSQL, stick with MySQL.
If you've used PostgreSQL before and have it installed on your server and PHP supports it, feel free to use it. Kusaba X has full support for PostgreSQL.
Further reading on MySQL vs. PostgreSQL can be found here
MySQL or MySQLi
MySQLi stands for MySQL Improved. MySQLi has been known to give better speed and performance than MySQL. If your server supports it (likely), use it over MySQL. If you get any errors connecting while using it, your server does not support it, and you must use MySQL.
To enable a feature, change its value to true
To disable a feature, change its value to false
To change the text value of something, edit the text that is in single quotes
For instance, if your boards name was Awesome, it would now look like this
Warning: If you plan on using single quotes in the name, you must first escape them.
There are several variables that must be set for Kusaba X to work. These are KU_ROOTDIR, KU_WEBFOLDER, KU_WEBPATH, and KU_DOMAIN. Read the comments that go with them to find out what to set them to.
If you don't use Apache, there are some things you'll need to know: