This thread connects to LST:
http://lsteam.proboards.com/index.cgi?action=display&board=help&thread=203&page=1Problem solved, thanks to Albafika and 2DaMax for suggesting me to replace stuff in a new common5, u two sorta had the same idea, sorta.
I've had this problem before, and a method that works for me is to export a CSP and import it again.
Give it a try, and if it doesn't work, I'm not really sure...
Have you tried resetting your PC? If not, do so.
If you don't want to re-add the files, you could try right clicking the "char_bust_tex_lz77" and export it, then re-open Brawlbox and try replacing the one the common5 you want to edit with the extracted one.