Hi Fred,To ensure a good connection you need to be precise with your cursor. To help you can try increasing the Snap Attach distance in Options | Snap | Snap Defaults. The distance is measured in pixels so the optimal setting depends on many things including your screen size, resolution and personal preferences. I find that values of 30-50 work best.
Use the Edit Node cursor (the second cursor button) to change the shape of objects - this will allow you to drag segments of doglegs to remove overlaps.