Table.php The main Object for each of your database tables generated by PHPCG where Table is the name of each of your database tables. Each Object extends the main Elements parent class.
Elements.php Main Parent class for all Table objects. Gets the table data (names, fields, ...) from admin/crud-data/db-data.json
table-filter-data.json The READ lists filters for each of your database tables generated by PHPCG where table is the name of each of your database tables.
table-select-data.json Used to build the select dropdown lists for each field, including relations & custom values. table is the name of each of your database tables.
db-data.json Main database values stored by PHPCG: items, table labels, object class names, primary keys, ...
nav-data.json The Admin panel sidebar settings with categories & tables.