How to import a plate from DXF
Add a new operation Stiffening plate, and for the parameter Shape select the option Polygon. Click on the button Dxf... and select your dxf file containing the plate outline shape.
Please note that the plate outline shape in the dxf file has to be exploded to the simple entities (line, arch), and the dxf file is not opened by other application.
Then click on the edge of the shape to pick up a line in the selection. You can manually pick up the other edge lines with the pressed Ctrl button or click on the command Consecutive in the top ribbon. You must select a closed shape. Then click on the command Outline.
The shape of the imported plate is drawn in the Details window.
In case there is an opening in the plate, pick up the closed curve of the opening outline and click on the command Opening.
To finish the import process, click OK.