When I start it I get the following messages:

memento: can't load library
pixeltango: can't load library
rradical: can't load library
toxy: can't load library
flib: can't load library
flatspace: can't load library
pidip: can't load library

and some objects like [range] and [expr] doesn't work anymore. I'm guessing this is related to the errors?

(btw, this is Mac OS X Intel version)

actually, not even stuff like [bng] works.

First, reset your preferences, you can do that in the Preferences, there is a new "Reset to Defaults" button. If that doesn't work, try throwing away your preferences file, its in ~/Library/Preferences/org.puredata.pdextended.plist