You have to set the LDraw library directory for LDView to match the one you use in Bricksmith. To do this, do the following:
- In Bricksmith, bring up Preferences (Cmd+,)
- The LDraw folder path should already be highlighted, but if not, highlight it.
- Hit Cmd+C to copy the path into the Clipboard.
- In LDView, bring up Preferences (Cmd+,)
- Go to the LDraw tab.
- The LDraw folder path should already be highlighted, but if not, highlight it.
- Hit Cmd+V to paste the path from Bricksmith.
- Hit OK.