The Multi-Curve tool creates curved path segments. You click to establish the initial anchor point, then click and drag to add a single anchor point and a curved path segment. Continue to click and drag to add additional curved path segments. Clicking determines the location of the next anchor point, while dragging establishes the curve.
While dragging, you can press the Option key (Mac) or the Alt key (Windows) and reposition the new anchor point. Releasing the modifier key with the mouse button still depressed enables you to continue shaping the curve after repositioning the anchor point.
The Xtream Path 2 panel offers the option of having the path's direction lines visible as you drag.
By default, each anchor point placed with the Multi-Curve tool is a corner point. To force a smooth anchor point, press the Shift key while dragging. As long as you continue to drag in a direction that produces a continuously-flowing path through the previous anchor point, that point will be converted to a smooth point. However, if the Shift key is down and you drag in a direction to prevent a smooth curve from being created, the previous anchor point will not be converted to a smooth point.
Example: