3D design problems w/ buildings (weird discoloration/ brightness)

This is a recurring problem that seems to have ruined the already 
onerous task of adding 3D objects to tracks. It would be great(ly 
appreciated) if somebody could suggest a viable solution, so I wouldn't 
have to bulldoze all the gazillion buildings created or pull the plug on 
this fruitless exercise.

Here's an example screenshot from one of the tracks: 
http://stcreativedesigns.fhero.net/img/stcd-build00.png

The red arrow points at the weird discoloration/brightness that appears 
on just about every building created on lots of tracks. Does anybody 
know what's causing that, and is there anything to fix? That happens 
with buildings of various shapes and sizes. As a hopeless experimenter, 
it's difficult to say what went wrong there. I tried "Optimize vertices" 
and "Optimize surfaces" for the whole building (group), no change. I 
also thought it might be caused by the stupid crease 45.000000 lines 
that always get added to the .ac file after you edit the track, but now 
that I went and removed all of that extra junk from one track.ac file, 
it turned out the same graphical BS (as seen in the example image) 
remained there. I've edited the various light settings (amb, emi, spec, 
shi) at the top of the .ac file and returned to the track, but nothing's 
worked.

So now, after these predictable failures, I'm looking for useful advice 
from more experienced 3D manipulators. This is not a graphics 
card/graphics settings issue: tracks without those 3D objects added 
don't exhibit that discoloration. Section "Graphic" in the track.xml 
file shouldn't be at fault, either: editing the light values there made 
no difference. And this only affects buildings, not for example 
grandstands or billboards.

I wonder if the surface manipulation of a building could somehow have 
messed it up: selecting a surface/surfaces, often using "Divide" to get 
smaller areas of the surface, then "Cut away object" (to be able to add 
a door or window), then naming that object and choosing some specific 
texture (mainly door or window). But if this method produces those 
graphical anomalies, how are you supposed to add doors and windows to a 
building? A separate rectangle placed in front of another object, like a 
door before a building, often caused ridiculous and disturbing 
flickering. Furthermore, there are buildings on these tracks with doors 
and windows added like described, and they, for some reason, don't have 
that bright discoloration. So confusing, so frustrating, so tiresome to 
bang your head against that wall.

More relevant info can be provided if needed. The .ac files, however, 
won't be distributed.

Sincerely,
stockroom staff
ST Creative Designs
http://stcreativedesigns.fhero.net/


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