Hm. How about simply placing some squares inside the compartments and put ambient on them. It wouldn't cast shadows of course, but the windows would appear lit.

Perhaps even put the ambient on the windows (thinking aloud here) so the glass "glows" - it would be for dark scenes only anyway - in daylight you can't see the lights inside a train (even if it's on) - I work in trains so I've seen them quite a lot LOL

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
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