One thing that is recommended is to never turn off Layer_0. All the Lights are on Layer_0, so turning off that layer, turns off the Lights and the objects turn black. It doesn't happen all the time in your drawing. If Layer_0 is already off, it will render, but turning Layer_0 on/off, it now renders black.
I also found that the pins within two Groups are on Layer_0, while the Groups are on Layer 3FS-5. I'm not sure if that makes a difference or not. No need to Explode the Group, just expand it (Selection Info) and select one of the ACIS Solid sub-listing. Layer_0 needs to ON to see the properties.
One way around this is to create a Lights layer, make all the lights visible, move them to this Lights layer, then make them invisible again. Now you can turn off Layer_0 without affecting the lights, but you may run into other problems while working with Layer_0 turned off.
« Last Edit: June 14, 2009, 09:46:08 PM by John R »
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