Amazing. After ten years+ of *NIX platforms, I didn't even think to look at the console!
Sure enough, gregpen, the permission for the Lame lib inside Switch wasn't set properly (good thinking!)
For the extreme beginner, I'll help you with a cool OS X Terminal.app trick:
Copy the Switch application /Applications folder
then,
Go to your /Applications/Utilities/ folder.
Near the bottom is the Terminal application. Launch the application --when a window opens up, type the following in it (or copy and paste)
chmod 755 /Applications/switch.app/Contents/Resources/lame
I'm using 10.3.9 on a dual 867 --it's working fine now and successfully converted many OGG -> MP3 files. There are a few gripes, like not being able to see the progress window when the app is in the background. Many Mac-only features, like key commands aren't supported. But, for a beta try for Windows programmers, it's not bad. Thanks and keep working on it, guys! 