Normally (and I have a feature bug request for this [BUG] Perspective: Ctrl+Mouse Select doesn't deselect components), in Perspective at the moment, with a component selected, pressing Ctrl and then clicking and dragging the component will copy it. Selecting a component and clicking and dragging on another component will move the selected component (it won’t move or select the other component).
However, Ctrl then clicking and dragging on another component won’t copy the selected component, it will move it instead.
Ctrl then clicking and dragging on empty space will drag a selection rectangle which you would expect to add components to the selection and remove components that were previously selected that are touched by the selection box, but instead it just selects components in the selection box and removes previously selected components.
Lots of inconsistencies that make developing very frustrating