If you click on the small red flag you can read the error. Now because the line is very long, I could just read part of it. But enough to find this page: MultiPipe component bug? what suggests it is a bug. However it also said, that removing 1 line was enough to solve this.
To find this line(s). I copied the multipipe object,
added two sliders 0<701 with two split lists. connected one A and one B output. with that I could narrow the range with the error from 534 to 535, that is just one line 534
In your version I culled this one line. and voila there is your multipipe.
Do not ask what causes this error, maybe still a bug.
But this is a way to get rid of the error.
So play with the sliders and see if you can find the error too.
Isolate the part you are working on and internalise data (so you do not need to upload a 3dm file. )
and upload this. Try to be precise as possible when formulating your question (most of the time more then 50% of the answer is formulating the question better).
NB: I understand this is a continuation of the question of this thread? Then upload here. If completely different stuff, make new thread with clear title.
