What I found is that it is the Reveal option you are using which is causing this.
With the other, simpler Reveal options, the lines are there.
Maybe the Library Part is not written in a way to take this case into consideration.
I would say this is a bug in the script of the Library part.
There is no workaround I can think of. I could not find a combination of parameters that would work either.
I will report this to GS.
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