Hello Rupert,
thanks for confirming the issue is resolved with note #1940845.
In the meantime I discussed the problem with the MOPZ colleague, who asked to always check note #1887979 for the corresponding notes to be implemented on the Solution Manager before generating the XML stack file. Note #1940845 is one of the listed notes.
I'm putting up this comment for all community to be aware of the solution.
Best regards,
Tomas Black