Unused Cross Section - Assemble Model Component

Hi there,

I'm currently encountering a small issue with the Assemble Model component...
I have connected two cross section components to the 'CroSec' input node and have flattened it.

The 'Elem' input node recieves a data tree in the format:

4640 values inherited from 1 source...

{0} N=8

{1} N=8

{2} N=8

...

{165} N=4

If I flatten the 'Elem' input node, all is well BUT It is essential that I keep the data structure unflattened for when I subsequently disassemble the model to retrieve line lengths. (I assemble and dissassemble because I need the lengths of all lines remaining after Karamba has removed excessively small elements).

I'd like to give an I profile to my beams and a tubular profile to my columns.

I've checked and double checked that all Beam ID's have indeed been attributed one or the other.

Strangely, if I use only the tubular cross-section for both columns and beams, no problem, the components behave. 

Solution should be quite straight-forward...am I perhaps flattening something that I shouldn't?

Would anyone have any tips for me to try out? Any feedback is greatly appreciated!

Nathan

ps: I am uploading the files but it's huge so will take a while! I have attached some screenshots below in the meantime.

UPDATE: Files: https://we.tl/y3ZzD7lS1x