I tried to make them from rare/unique/magical items, because I wanted the things they already have, and then add more (add the runeword in addition to it)...
I went over the docs bunch of times, but it seem like every time I missed the part that came after "Grey items only!"

I kinda ignored it every time because I was like "I wanna use it on good/strong items, not regular/grey items (to gain more of it)..
So now I feel a bit confused here.. Since runewords are so strong, why would you even consider using all the other items(magical, rares, uniques and so on)?
Kindly forgive my ignorance..
PS: Unrelated but, is there a way to change the colors somehow? I am blind color and I find it very hard to tell the difference between the Yellow and the Gold ingame colors..