My experience with titanium was really poor. Lots of silent fails with no real error output. Also I found it very limited, more limited than just opening a webview and using html5 really and hooking into it with code for the native functionality.
As for error output - you just need to look at the logs in detail (and turn them up to trace) to get details for hard crashed.
What exactly would you do if the client came back to you and requested something titanium couldn't do?
When I was using it it had problems even moving to a page with a webview already loaded up to a webpage.
Have you built a project with a real native language for pay?