Nice script. Nifty that you made it compatible with all 3 RGSSs.
A little tip in REGEXP, and it barely matters, but instead of [0-9] you can just use \d, i.e.:
You can also make it case insensitive if you add an i after the slash at the end.
Again, nice and nifty script. My only other tiny problem with it is that you overwrote the set_text method. While it's not that big a deal, you could've done the same thing just by going:
alias coloured_descriptions_stxt set_text
def set_text(t = '', a = 0, *args)
t.gsub!(/\\[Cc]\[([0-9]+)\]/) { "\001[#{$1}]" }
coloured_description_stxt(t, a, *args)
end
Not 100% that would work though... :S