So I basically followed this thread's instruction to get Colemak to work.
My keyboard (HP bluetooth keyboard), however, does not generate a separate .kl file in the keylayout folder. So I tried editing Generic.kl. It worked, and the keyboard is now Colemak. Korean keyboard, however, is now messed up. Keys are moved around because I changed the layout from Qwerty to Colemak. It seems that Korean keyboard relies on layout being Qwerty.
I appreciate any help.