The patch is done! Only minor C# script patches were needed, it was just a matter of carrying over what I did in the original game to EXTRA1, so nothing interesting to tell. I'll try to edit the main post to make it look cleaner when I have time. In the meantime there's good instructions on the README file that allow you to even run it under Steam on Linux with full integration working.
NOTE: The Linux patch is to be installed after installing the official 1.01 patch (which was released some days after the game's release), either automatically by Steam (make sure you don't have any pending updates), or if using a non-steam version, by using the installer they provide here (click here) (to avoid going through Wine, the installer can be manually opened with tools that can open NSIS installers, for example 7-Zip, then it's just drag and dropping into the game's root directory). If it works correctly, you should see "1.01" or "1.01 (Steam)" while running on Linux.
Base patch: http://www.mediafire.com/file/5qkd4az69yytqe0/AokanaExtra1LinuxPatch_1.01.zip/file
English videos (these play when you play the game on English/Japanese - not needed if you will play in chinese): http://www.mediafire.com/file/5h53tkbjz7wwatk/AokanaExtra1VideoFilesEN.zip/file