Update: Download CPKREDIR. Bonus: ExtractCpkMod, can be used to "convert" modded CPKs (extract only new or changed files), or to just normally extract CPK files. The current version supports Sonic Generations and Lost World. It might also work with some more games (like Sonic 4, but not terribly useful there). The cpkredirInst.exe program included in the package can be used to "install" or "uninstall" CPKREDIR. Basically, it patches a game exe so that it will load cpkredir.dll. It will try to patch any exe you provide as argument (e.g. drag & drop an exe onto cpkredirInst). If you don't provide an argument (e.g. just run the program), it'll look for SonicGenerations.exe or SLW.exe in the current folder. If you don't want to patch the game exe, you have to use the included launcher, DllInjector32. It's a little program that can be used via command line / console, but it also has a simple GUI. Its purpose is to launch another program while injecting (=loading) one or more DLLs for it (I.e. cpkredir.dll) into memory. Note that this will not work for games that must be started by their own specific launcher. Sonic Lost World is such a case, it must be launched by Steam or it won't run. If you have questions, just ask. Original post: If you're reading the Sonic Generations Hacking topic, then you've probably already heard of CPKREDIR. If not, then it's about time. After having written a pretty lengthy documentation for the thing (included in the download), I'm going to be brief here. CPKREDIR intercepts CPK file read operations by Sonic Generations and redirects them to external files. This makes it possible to have the game load modified data files without the need for unpacking and repacking those large CPK archives every time. Internally, CPKREDIR actually creates virtual CPKs on the fly, or rather their most important data structures (header and table of contents). Those virtual CPKs are presented to the game and when it tries to read from them, the requested data is fetched from the original CPKs or from external user files. Download the latest version 0.41 here. Download the latest version here. It comes with some files that let you play Dario FF's "Classic Sonic Adventures", after downloading his fixed files. Dario, I hope you don't mind. Some screenshots of the console logging window with CPKREDIR running a combination of Melpontro's Wave Ocean and Megamaniscrazy's Shadow mod: Feel free to ask any questions about it here, or let me know of bugs you encounter.