Hello, again thank you very much for your work.
I've been testing this new function and found an error.
When I enter an expression in some field of the original part spreadsheet, for example =Pad.Length (first image), the assembly spreadsheet shows an error (second image).
I think this is because when you build the spreadsheet in the assembly, you can't evaluate the expression and therefore show an error.
I think you can try the following solution:
1) Evaluate the recursive expression of the original part spreadsheets when creating the spreadsheet in the assembly. This way, you could get the result in a string and not generate the error. This could be done by identifying the = sign.
Look at this post I created https://forum.freecadweb.org/viewtopic.php?f=3&t=32004
Greetings