Never mind. I give up.
So far something has gone wrong every step of the way and it's just too much of a hassle. Mac installation failed and won't let me reinstall, Windows installation failed to detect Java, Java reinstallation failed to be recognised by the system, apktool failed to install the framework, apktool failed to decompile the apt, apktool then fails to build the modded apt. Every step I've had to manually fix things and it's simply too much trouble for just changing a few strings of text on my device.
With a track record for having problems absolutely everywhere, I just uninstalled and deleted everything in case the next step blew up my computer or something.