cant run from in game

[R3kandH4V0k]

Good afternoon, I added this to a 1.10.2 pack I'm working on. I followed the steps, (download and put into mods folder) I tried the command /extTweaker in game and nothing happened. I'm not sure if I'm doing something wrong..

[yujukitten]

I am having very similar issue "an unknown error occured while attempting to perform this command"

Did you ever resolve your issue?