It's fine I'd understand. I realize this is a lot of information, but I'll give it a go.
Regarding the editor's, as far as I remember only the one's shown in this screenshot should be layed out properly, the others may not be completed or do anything.
I am really interested in working on this IDE again and adding the actual logic. But there's some things I have to straighten out first. With this new LGM release I am also writing the GMX API in C++, which is a reusable library for loading GMX projects. This is needed in NaturalGM, and C# can call native code, so I'd just use it instead of rewriting it again in C#.
The basics start with the language. In C++ you can namespace things. And you can nest namespaces in other namespaces. The namespaces are resolved with the :: operator, such as std::string.
In Java, there are no namespaces, only packages. Packages follow the naming convention of a web domain name, except reversed. So if ENIGMA was creating a package, we would use the package name of org.enigma-dev.somejavapackage. When you do not own a domain name you can use things like your GitHub URL where the project is hosted. Each Java file in a package has only a single outer class. You can not have two outer classes in Java that are side by side. You can nest another class inside the outer class, called an inner class, but it can not be side by side. So it is 1 main/outer class for each *.java source file. You can't even put a single enum next to the outer class, must be inside it. These packages correspond to physical folders on the file system, as opposed to C++'s and C#'s being just in the actual source files.
This limitation does not exist in C# because it follows the C++ conventions of namespaces. You can put multiple classes at the outer level side by side. So I genuinely believe that C# is a superior language for many other reasons in addition to this, including the way it handles templates and generics.
So all that exists there are the designer files. The designer file is just where the WYSIWYG tool to place controls puts its code for creating them. You can write that code yourself in your own classes, which is what is done in LateralGM. Other frameworks like Qt use their own designer files which are compiled to C++, in JavaFX or WPF you use XML files. WPF does the styling in the XML, but JavaFX and Qt use separate CSS files to style the controls.
So we have the designer file generated by Visual Studio:https://github.com/enigma-dev/SharpGM/blob/6719388fb7cabcdffefe69e4f5f8e38deae756de/SharpGM/MainWindow.Designer.cs#L26
Contrary to what it says, you can actually edit it from code as long as you write the exact same code as the editor would. Also, people often complain about this way of doing layouts because XML is more flexible, you can keep it outside the executable and let end users change the layout, so people often argue that WPF is the way to go. But when people write native Win32 apps using C++ and plain old Windows API, they do it in resource files, which I'll get to.MainWindow.cs
Then you have the regular source file, which is where you should add the actual logic. This includes events for the controls and everything.https://github.com/enigma-dev/SharpGM/blob/6719388fb7cabcdffefe69e4f5f8e38deae756de/SharpGM/MainWindow.csMainWindow.resx
Finally we have the resx file for the form.https://github.com/enigma-dev/SharpGM/blob/6719388fb7cabcdffefe69e4f5f8e38deae756de/SharpGM/MainWindow.resx
This file is XML and the comments give you a good explanation of what it is for. It is essentially an extension of the rc resources file for WinAPI. When you write native Win32 applications like I just mentioned, using C++ and the plain old WinAPI without .NET or anything, you use rc resource files. ENIGMA uses these for some of the basic message dialogs, such as get_login or show_info.https://github.com/enigma-dev/enigma-dev/blob/715e96c3b17af346d68e37a8c1708cc13cb369f5/ENIGMAsystem/SHELL/Widget_Systems/Win32/getstring.rc#L14
Notice it looks like a layout? LTEXT is just a label. It tells you its position, dimensions, and text value just like a layout file would. Anywhere you see #include <windows.h> that means the Windows API is being used. These files go through what's called the resource compiler (MinGW, the Windows port of GCC, has an open source version that ENIGMA uses) turns these into a binary which the Windows API can read.
All of this gets wrapped up for you with .NET, including the native controls. Everything in Windows Forms and .NET is just C# bindings (called a language binding because one language is wrapping another languages code, C# wrapping C++ ie) around all of this that takes care of the work for you. resx is an extension of these native Windows API resource files that is formatted as XML.