Mrbaze, just checking here, but did you try Fred's suggestion of using "object isolate" instead of layer isolate? Once I discovered this command, especially with C3D objects, I'm happy not to use layer isolate again.
Matt Kolberg Cansel - Autodesk Division http://www.cansel.ca/
Personally most of my C3D objects are also on Layer 0 and I just change the style to No Show as required.
However to provide further input, (I believe this was mentioned already) that you can set all the entities to Layer 0 and the C3D block to (for example) ALIGNMENT1. This way if you turn the layer ALIGNMENT1 on or off, all entities within that C3D block will behave similarly to the block, as if it was on the same layer.