Rest assured I have checked and double-checked the layers in question, and there is no effect selected anywhere that should result in this, as far as I know.
As a test, I tried scaling the object, and found that the effect was more pronounced when scaled down, and less when scaled up.
As another test, I turned off scale compensation in all layers, and the whiteness persisted, though some of it was drowned out by the now-thick outlines which also rendered the object unusable.
LM, any idea what could be causing this? I've attached an image that shows the effect - the fairy in the middle is at 100% scale.
