The plugin in your ActionReplay folder is called ActionReplay.plg, right? As far as I'm aware, that is the only case in which it should not be plugin.plg. I don't know whether case matters or not here, but that's how they were written in the main post and what I went with. That your .txt file seems to be erasing itself is odd, and something I have no clue how to help with. Other than that, all I can say is to double check your paths carefully and make sure you're not missing a character.
Yeah it is called ActionReplay.plg. I even tried the TitleID Folder -> with cheats.txt and plugin.plg.
I did find out why the textfile ended up with a 0 filesize. I hit ActionReplay thinking the codes may appear there and hit the + which must have erased what I currently had.
Or upload your text file(with cheat codes) here cuz maybe it has something to do with the codes.
Umm... I got the text file the github