Hi C Deho
I've replied a few times to this and received an odd error each time...so sorry if there ends up being multiple copies of basically the same answer.
Anyway, the stiffness matrix does not use node IDs. Nor does the force vector - it uses the degree of freedom IDs. In any case yes, the IDs used to solve differ from those that WB Mechanical shows us for the mesh. Hence the need for the vector of ID mapping.
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