Plugin seems outdated.

And before anyone goes “Can you even read? You didnt follow the readme” yes I did.
So to recap
– Downloaded the .zip on separate machine
– Unpacked
– Opened Readme
– Opened db-config and according to the db-config itself, it uses the definitions from wp-config.php, so actually according to the file no changes is technically required.
– moved db.config.php into root web directory next to wp-config.
– moved db.php into wp-content.
— Attempted first-time install (page appeared)
On step=2 there are tons of WordPress Database errors indicating “bad default value” for pretty much everything.

Therefore unable to first-time login as Admin, as the admin user was not successfully put into the DB by HyperDB itself.

The db.config contained a singular configured DB (localhost) and yes, both read/write as 1.
Wordpress works excellently when the plugin is taken out and these insert errors only appears when db.php and db.config is present in their corresponding folders.

Somewhat likely the plugin here is outdated for the newer versions of WordPress/Mysql.