make a new colourscheme in "steam/steamapps/common/App Game Kit 2/Tier 1/Editor/data/colorschemes"
(copy an existing one is easiest)
change line 34
"comment=0x######"
to
comment=0xff0000
ignore the 0x and change the #'s in pairs
00~ff is the colour strength in RGB
so
0xff0000 is red
0x00ff00 is green
0x0000ff is blue
etc
you will also need to adjust line 2 to a suitable name so it shows up in the list (i just named this the same as the new file name).
to now find and change the colour scheme open AppGameKit -> view -> change colour scheme
life's one big game
spec= 4ghz, 16gb ram, AMD R9 2700 gpu