I&#x27;ve been using QML for 3 or 4 years now. My answers are tainted with experience.<p>1. JavaScript: is there only to facilitate manipulation of Items and elements. Use C++ for any logic<p>2. Deployment: Yes<p>3. Size: Yes<p>4: This sounds like you&#x27;re doing it wrong. IDs are scoped to their context (usually the item and on down)