Click a part: its dimensions open on the right. Drag: rotate · Shift/right-drag: pan · Wheel: zoom · Double-click: reset. Reloads on its own when the file changes.
Click a part or a tube: it opens on the right, edit it there. Drag a part to move it on the drawing. Seen from the right (drive) side; dashed = on the left side.
Click a wire, a Pi pin or a breadboard hole: it opens on the right. Holes in one numbered column (a-e or f-j) are joined; so is each rail.