Adobe removed Flash Buttons from DW CS4 for web accessibility reasons. Flash navigation is not web friendly. Try using CSS styled text links or the built-in CS4 Spry navigation tools.
FREE CSS menus.
List-O-Rama (DW Extension)
CSS Express Drop-Down Menus (tutorial)
CSS Tab Designer creates 60+ CSS Styled Button and Tab Menus (download)
CSS Menu Maker (On-Line Menu Generator)
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