Round shape corners using the fillet radius option
Curve a corner of a drawn shape by setting the Fillet Tool's edge length reduction and applying it to two adjoining edges.
To curve a corner of a drawn shape (for example a panel's outline in Construction > Edit Shape), use the Fillet Tool and set its value in Fillet Preferences: the field is 'Edge length reduction' (default 100), the length taken off each of the two edges that meet at the corner; at a 90° corner it equals the arc's radius.
With the Fillet Tool on, click the two adjoining edges (for example the top edge and the right edge) to round the corner between them, then Apply. The size is set beforehand in Fillet Preferences as 'Edge length reduction' (the length taken off each edge; at a 90° corner, the radius).