Application.prototype.launch() not being triggered when compiled

I tried many hours, if not days - but cannot get the launch method of Ext.app.Application triggered, once compiled - also tried every possible combination of autoCreateViewport true/false/reference - while the viewport just won't render - only when I call Application.prototype.launch() from the JS console.

Refering to ExtJS v5.0.1 with latest Sencha Cmd... while this problem not exists in v4.

Is there anything which I might be missing?

Application.prototype.launch() not being triggered when compiled