The application “SomeApp.app” can’t be opened

After extensive trial-and-error, and a lot of fruitless Googling, I found the solution required modifying the executable status of the "inner" application file. This line: chmod +x SomeApp.app/Contents/MacOS/*

Fixed the problem in all cases that I observed. The +x flags a file as executable, and the only file in the /Contents/MacOS/ directory is a binary representing the actual file that should be executed when you double-click the application (a .app file is really just a folder).

Hope this helps someone else!