I also struggled with too much green for weeks on end with my Optoma HD25-LV, tried dozens of combinations of settings, and at one point just gave up; no matter what I did, I couldn't get rid of green skies in color movies. Then I decided to throw calibration to the winds and simply changed the default color temperature from Warm to the coolest setting. Everything looked vastly better and I had the blue skies I'd been missing. I have made a couple of very minor tweaks since then (boosted the contrast from the default a bit) but basically the 3D default settings were fine (other than the Warm color temperature). I also turned off Brilliant Color (I don't remember right now if the 3D default uses BC or not and it's late, so I'm not going to power up my projector to find out!). Hope this works for you.
To my surprise, I found that a black-and-white 3D movie such as CREATURE FROM THE BLACK LAGOON was a great test for my color settings. If the picture doesn't look black-and-white (too much blue or green or yellow), then fiddle with the 3D settings until it does. Be sure to have your 3D glasses on when experimenting since the ideal 3D picture will have a slight bluish tint to it in 2D only (meaning the double-image version you see without the glasses). Your yellow-tinted 3D glasses will compensate for the bluish tint that you will see in 2D when you remove the glasses.
Recent Optoma projectors allow two different saved settings, one for 2D and the other for 3D, so these adjustments shouldn't impact whatever 2D tweaks you may have already made. (I can't speak to 2D settings as I only use my Optoma projector for watching 3D; I use another, older projector, a Mitsubishi HD3800, for all of my 2D viewing.)
Last edited by fxrh; 01-01-2015 at 11:43 PM.