The main editor consist of tabs that you use to switch between various systems of plyGame that can be edited. These include not only project related settings but also systems that might be specific to a certain genre of game. If you do not want to use a section, simply ignore it. This documentation covers only those systems that are part of plyGame core but you might notice extra tabs in the editor window if you installed 3rd party plugins.
The Editor window can be opened from the Toolbar (gear-like icon) or menu: Tools > PLYoung > plyGame > Main Editor.