Hey all,
I was having the same problem as many and found a fix. It seems that Novacom is not running correctly, and I couldn't get the SDK to find the device either. If you run novacom via terminal first, WebOS Quick Install finds the device right away. Follow the instructions on this page and hopefully it will work for you too! Gets novacom working before you run the app. If this was previously posted in the thread please forgive me. Got it working immediately!!!
Good luck!!!
Palm Pre “Novacom Not Running” error on Mac OS X « TheJeffFiles.com