Might not be exactly what you want.
Create morph planes for the circle and square, in the same plane (i.e. one inside the other).
Then union them so they are one.
Now you can select one of the surfaces and reposition it.
See image.
The only other way is to manually place the connecting lines and then solidify or cover with faces maybe.
Also a ruled shell can do this and then convert to a morph if need be.
Barry.
One of the forum moderators.
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