For the most part Chat, ChatHandler, WorldSession, AccountMgr, files were the most important. After those files it is pretty straight forward on how to fix the rest of the errors. I went through some RBAC errors in Player.cpp to show everyone how to do it and less hard it can be. Since you followed everything in the video, you can compile to see the errors left to fix. You will still have more errors to fix in Player.cpp, All the command files, etc - but the most important portions of the RBAC removal I went through in the video. I never said that was the end of getting rid of errors in the video.
People need to learn how to get rid of errors themselves, it can't be handed to people. If I went through every single error, the video would be way too long and I wasn't going to do that despite the length. Double click the errors, read the permission data type to see what security level you think it is for and supply it with a security level.