Hi Matadem, in the steps that are listed there, it has step 3 as:

3. Trace the bitmap with pstoedit and export a dxf with potrace

You can probably import that DXF into MoI to get the profile curve, then inside MoI use Construct > Extrude to extrude it into a solid, then Transform > Deform > Twist.

In the description for potrace (https://potrace.sourceforge.net/) it also says it can generate SVG or PDF output as well. These should also work, try those if DXF format doesn't work.

- Michael