I created a test case. I dragged a color bar png into PowerPoint. Saved the slide as a png and loaded it into EW. I also loaded the PowerPoint into EasyWorship. Then loaded all three up side by side. I've attached a screenshot of my results.
I'm wondering if there is something going on with the video card driver. Maybe a clean uninstall / reinstall of the video card driver may solve the problem. I've seen things change colors due to the video card driver making color changes during 3D (DirectX) rendering.