From Sonic Retro
Welcome to SonED2, the Sonic the Hedgehog data editor. SonED2 contains all the editing features of the original SonED along with additions and improvements. Unlike the original, however, SonED2 edits individual files, which means that data has to be extracted before editing, and then reinserted when editing is complete. This allows the user to have more control over their data layout, and also allows for making changes, additions, and deletions that alter the data size without having to worry about an automated system overwriting other data or leaving unused gaps.
Because SonED2 edits individual files, it is "project"-based, meaning that it is necessary to create a "project" file describing what data files should be loaded. "Project Files" are plain text files, although they are given the file extension .sep to identify them to SonED2 and the user. These files contain the filenames of the data files required to begin a particular editing project, and a few settings values when necessary. Different types of projects use different formats for the "Project File", which are explained by the "Project File" documentation.
At program-start, a logo screen is presented as a placeholder until a "project" is loaded. Using the file menu, open a "Project File", and if the data in that file is correct, the appropriate editor will start and the data referenced by the "Project File" will be displayed and ready for editing.
The "Save Project" selection will save all currently loaded data to the files specified by the "Project File" that was used to open them. For reference, the path and filename of the "Project File" are shown in the window's titlebar. The "Project File" may be altered before using "Save Project" if different names are desired. (Pressing F3 will also save the current "project".)
SonED2 will function in a window or in full-screen mode. When an editor is active, the "Editors" menu contains an option to switch to full-screen mode. The F4 key may also be used to switch into or out of full-screen mode. It is the only way to switch back to windowed mode. While in windowed mode, the menu and scrollbars are available. To turn them off or back on, the F2 key may be used.
For editing specifics, please refer to each editor's documentation.
This is an advanced tool for advanced users, so less experienced users shouldn't expect to delve straight in without having a few problems. Reading and understanding all documentation is essential.