Export settings in lightwave give you a choice to limit the size of the images when exporting, make shure that is off. I find problems when exporting images larger than 1024x1024, so what I do when I need more rez is to split the panorama in two images so that each is 1024.
The fog setting is also something you can turn off while exporting, and once in director too. I am not so sure it's fog that is giving you that particular shading tho.. remember you have no shadows in director, so things under other things can appear bright unless you bake everythng first, which is what I do. Those arches where you enter your castle looking thing just beg for some baking because it's hard to make out the exact shape without shadows.
Looking at your image I see that you skimped on polygons quite a bit on the cans, polygons don't affect shockwave performance much unless you really go nuts. So up the polycount on those, polygons don't stress modern computers much and take up very little bandwith. Tiff images on the other hand..