AutoCAD 2008 User's
Guide > Create and Modify
Objects > Create and Use
Blocks (Symbols) > Add Dynamic Behavior
to Blocks > Add Dynamic Elements
to Blocks > Modify Dynamic Block
Definitions >
Modify Dynamic Block Definitions
To open an existing dynamic block definition in the Block Editor
To delete an element from a dynamic block definition
To modify an action's selection set in a dynamic block definition
To redefine a stretch or polar stretch action's stretch frame set in a dynamic block definition
