That language switch is working smooth so far, thanks for providing.
What do i have to be aware of when doing a productive build?
Just copying the Ux & locales folder into the build/production doesn't seem to do the trick 
In app. js I added:
Code:
Ext.Loader.setPath({
'Ext': 'sdk/src',
'Ux' : 'Ux'
});
The error console of the production app says only this with a blank app screen:
Code:
index.html:65Error evaluating file:///Users/macbook/myapp/build/production/app.js with message: SyntaxError: Unexpected token ':'
However, if i build the app without the "Ux" : "Ux" loader config, the app loads fine, just without any Ux support and this error console message:
Code:
TypeError: 'null' is not an object (evaluating 'a.title')
thanks for any hints...