Create coplanar faces from curves

Hello, I’m trying to convert several curves to polygons for making extrusion. I have a SHP file with buildings and heights, the buildings are imported as curves. But with the Surface boundaries component i only get one surface, it ignores all the coplanar lines.
this is the highlighted curves:

This is the highlighted surface i got:

i only could get a better result to what im trying to do, extruding only the curves.

i have followed this guide if someone interested.

this are the files.ANÁLISIS DEL (761.0 KB)

anyone has a good solution for this?
Thanks a lot!

If you are OK with a WIP (I have a “similar” case) solution like this I could elaborate more and provide something that could make real-life results (the big issue: Elapsed time).

As it is (10 minutes work): does NOT cluster the related Curves (that’s critical), has a lot of missing things to consider/check (most notably: curves are node to node and no ccx events are computed) … blah, blah.

If you opt for a solid result the height is taken from area*areaFactor.

Check the input demo Curves to see what I mean. DO NOT attempt to use your data on this thing: is just a hint. (127.6 KB)

Nice. Would be usefull for open curves. thanks for the hint!
i already solved it using @it plugin, had some problems at first but now its working.