On some versions of Mac OS X, double clicking on Vectorworks palettes such as the Resource Browser, will not collapse or expand the palette as expected. This is controlled by a Mac OS X preference pane.
To correct this,click Apple > System Preferences, under the "Dock" pane, make sure "Double-click a window's title bar to minimize" is checked.
Once this is checked, restart your machine and Vectorworks palettes should behave as expected.
Note: This option is not included on OS X 10.7, however it is available in OS X10.8 and OS X 10.9.
Edited by JimW