Thank you for clarifying!
I may be wrong, but my current understanding is that the VCV-native ‘Save selection as’ mechanism actually saves the mappings but strangely cannot recall them.
In contrast, STRIP++ can recall the mappings even though it was not used to save the selection.
There is a brief explanation for using STRIP++ that works for me.
STRIP: Ahh, now I understand that the .vcvss extension is a STRIP preset. It works after reading your explanation, thank you!