Arc centers and endpoints can be useful to dimension the radius or diameter of an arc. This setting can be toggled in the CAD Defaults dialog.
There isn't a way to convert a digital image into a 3D model in Chief Architect; however, you can use an image of a floor plan as a template to trace over.
Missing data from .dwg or .dxf imports can be a result of version compatibility, paper space, x referencing or unsupported formats.
The Fillet Two Lines and Chamfer Two Lines edit buttons allow you to add fillets, or curves, and chamfers, or angled edges, to the corners of CAD objects.