Many thanks guys, you all gave me quite interesting suggestions. I'll explore most of them regarding the stability and "compactness" of the final solution as regards the deployment.  

I have one really silly question - when you create an app (with Spec2), how can you made it start automatically when the image starts, and avoid displaying the World? I browsed through many of Pharo books and documentation recently and cannot remember if this is mentioned anywhere.

Best wishes,

Tomaz