I would avoid green concealers. You end up putting more makeup on the spot than you normally would and it ends up looking cakey. Try using the clearing petit BB cream from Holika Holika for either individual spots or for allover coverage. It's good stuff, and is great as a concealer. I still use it when I want my freckles to be less visible, though my skin is clear now.

I have tried the make up forever and all the base products oxidise, thats why you see the orange hue. It also gets darker on face by time. My scars are also stubborn, so here is what i use. The best coverage is from bobbi brown stick foundation. I use it topically and its not noticeable at all. You can apply it with fingers. Then, as the bobbi brown is expencive, i use the matte mousse make up from essence. Applied with brush gives a total coverage,if you use fingers on that it gets more sheer, so always brush. For last i reccomend you the coverage cream from artdeco. It is a small amount but soooo concealing. It is formulated to cover tattoos. A little goes a long, i use it to cover more recent scars or active pimples. Fingers to apply that, too. Good luck!