I have tried this approach and find that the sketches imported from OpenSCAD DXF files are overly complex and very slow to project and extrude. In addition, I found a similar problem when using FreeCAD Shapestrings to generate the text.
Given the elegance of the Shapr3D user interface, I am hopeful they engineer a better approach in the future. For example, perhaps a solution using SVG files generated by many programs on the platforms Shapr3D supports.