I feel silly, I downloaded ReadbatteryLevel, extracted it, didn't find the variables with threadstack so I used Cheatengine to locate 'em, and I put them in Readbatterylevel.ini
I then downloaded VoidBattery.ini and the read_file.lua, compiled a skin for them and I keep getting 0%. Did I do any of these steps in the wrong order or did I miss something obvious? Thanks for your time!