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(Changing a block's contents) You can use any editing or node editing tool to modify, move, copy, add, etc. objects that comprise a block. This example use the block shown below, consisting of four objects. The block name is "Logo."
- In the Blocks Palette, select the block, and click Edit Content.
- In edit mode, the screen contains only the block components, which are available for editing. You can add, delete, or edit objects. Whatever appears on the screen will become part of the edited block.
- When finished, right click and select Finish block/group editing, or click Finish Edit Content in the Blocks Palette.
The icon for the block is updated to reflect the edited components. Any instances of the block already in the drawing are updated, including resized and scaled blocks. 
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Relocating a Block Reference Point
Hotkey: Ctrl+Shift+R
A block is inserted by placing its reference point. By default, the reference point is at the center of extents of the entire block, but this location can be changed.
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