Macros have a character limit of 255.
The one I posted is exactly 255 characters long; Vrul rewrote it to be 234 characters which leaves you with 21 characters which is just barely enough to color one of the strings.
You asked why your macro wasn't working but didn't post it, so we have no way to know what's wrong with it, but odds are you exceeded the character limit.
This will color it but is presumably what you already have.
Lua Code:
/run local d={982,1,982,2,982,3,983,4,983,5,983,6,984,7,984,8,984,11,985,9,985,10,985,12,986,13}for i=1,#d,2 do local n,_,x=GetLFGDungeonEncounterInfo(d[i],d[i+1])print(GetLFGDungeonInfo(d[i])..':',n,(x and''or'\124cffff0000not ')..'completed')end
For anything more complex you'll either need to run an addon that lets you write extended macros, or turn this into an addon.