Not sure what you mean by it works on a cube in the lab but not on the real thing. Could you post a screen shot of the lab settings you're using on your wings model? One thing I can think of, is if the third box in the lab doesn't have any bump texture, like if its a solid grey then you won't get any bump no matter what number you set the bump to. Same if the dot isn't in the right channel. but without a screenshot I've got no idea :(