Hi Alma,
If you updated LR using the CC manager, the program will not run. You have to uninstall it then go to to this Link http://download.adobe.com/pub/adobe/lightroom/mac/5.x/Lightroom_5_LS11_mac_5_5.dmg download it and reinstall. Then open the CC manager and you'll find LR 5 has been updated. Also, you'll need to follow Scott Thomas' info above to make sure your plug-ins are working.
Dennis
