I have checked and rechecked my file pathing etc; I'm getting no errors and everything is where it should be. I'll post some pictures in a bit; any help would be appreciated. My mod still isn't appearing under the tuning pack dropdown.
Might it be something to do with Windows 8.1, the version of Java I'm using...?
You can check for \Documents\my games\Company of Heroes 2\warnings.log file for errors, but I expect you need to remove the .mod file from the info section.