It allows for soft replacement of any file (so without touching the original files); for individual texture replacement (so textures mods are now compatible with each others and smaller in file size!); and for other small features like cheat codes, automatic mod updates/install, etc.
InstallationDownload the mod manager from here or from the GitHub page, extract all of the files directly into your game's directory and run the manager. It will prompt you about installing the mod loader. Installing only edits ubi.ini.
The Mod Loader will prompt you for both manager and mods updates. To disable automatic updates check the "Options" tab.
DocumentationTo download mods, simply extract them in the "Mods" folder, to create one use the + button in the manager. You can also go in Options to enable the URL handler and use the 1-click Installer from GameBanana.
See the wiki on GitHub for documentation on creating mods (file replacement, DLL injection, update system, and more.)
In short you can replace any file from the original game by placing them in your mod folder with respect to the game's hierarchy. If you want to replace the main texture file entirely, just place the new "Textures.cnt" in "Rayman2/Mods/yourmod/Data/Textures.cnt". The mod loader supports individual texture replacement, just create a "Textures.cnt" folder for example, and place the gf files there using the same hierarchy as within the archive. Please keep the original resolution for now.
For more detailed information, please read the wiki.