Hello
first it could be interesting to know why it didn’t work for you. Are you on Mac ?
this is not a so simple job. There are some discussions related to this subject but to my knowing there is not free or available tools at the moment except Bridge Curves.
You’ll find elements of information there
and there what I did
In order to be able to make a quite robust tool for real life objects with many holes and thin walls I had to make many tools in C#. Everything is on a library and also began to put that on a plugin I intend to sale. But I am not ready. End of the year.
The advantage of making a robust library (base tools are RhinoCommon and Clipper) is that it is then quite easy to implement extension like the one here
I saw in your script that your sort by area, that is not the good way of doing.
You could recursively by looking which curve is inside another. You will end with a tree
the trunk is the exterior. If there are many trunks it means you could not make a single line print (I think it is what you are after).
After for each curve you’ll have to track the position of the bridges. A curve could bridge more than one curve… It took me 2 weeks to have a good tool that I hope is used to make real things (surfs).