Thank you @Dimitar_Venkov!
Your explanation works for a two dimensional list (a list of lists), however I can’t get the Group Curves node to work for a three dimensional list (a list of lists of lists).
See image:
floor holes.dyn (39.6 KB)
The top graph is operating on one solid, whereas the bottom graph is operating on three solids.
I’d like to avoid flattening completely, otherwise the data-structure of the curves will no longer match MassFloors and levels. Each floor must be placed on it’s appropriate level, rather than ‘Height Offset from Level’.
I’ll just have to find a way to make sure the lists can be re-organised afterwards.
P.S. as an aside, how is list lacing relevant on a component that only has one input (such as Curve Group? using the @level makes sense to access inner lists, is that what Longest list lacing is doing in this instance?