1. Select File > Place to place an image file. (Select the 'Link' and 'Template' checkboxes.)
2. The file is placed into a new, template layer. Notice that in the layers palette the new template layer is marked as being targeted (indicated by the little colored square to the right of the layer name), but the layer above it is actually hilited (selected).
3. Selected the pencil tool and drag over the image.
4. Illustrator gives an error: "Pencil or smooth tool: Unexpected exception. Error: NESS"

The program doesn't crash or anything. I think it has to do with that a locked template layer cannot be targeted, but after you place the image, it is actually being targeted automatically. If you select another layer and THEN draw, it is fine.

Illustrator CS
Windows XP Pro