The number of imported objects, DEMS and phototextures are of most influence to saving. A scene with 10 phototextures and 10 objects can take longer to save then a scene with 1000 objects and a simple DTE-texture. I don't know about the numbery name. I can't remember getting files named like that. I quess I'm not much help, but maybe my $0,02 gives someone else an idea for a better aswer.

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