I have often found the Arc CAD tool difficult to use if the radius of the Arc is large , or if the center point is not explicitly defined. This new plugin creates Arcs from three points: a start point, a point along the Arc and then the end point.
Part of the code has been derived from the "Dimensioned Objects" plugin as provided by EddyCurrent

Feedback and any bug reports welcome
Geoff
Vers 1.0.0 is attached.
Vers 1.1 is attached - adds option for Circle from three points.