Takes me days and I still can''t figure this out.
I have built an Sencha Touch 2.1 app with an extension from Sencha Market. I can build the app with Sencha Cmd 3 with the flag v2deps set to true. After I run the build (testing or production), the app acts differently and I got an error:

Uncaught TypeError: Cannot read property 'title' of undefined
on this line of code
this.container.add(Ext.merge(this.config.defaults, item.raw));

Since it is a straight build, I assume no code is being changed. The non-build one is working 100% fine. Does anyone encounter similar problem?