This started with post 36956 but whilst I admit some failings I now confidently report that some of my misunderstanding is from a bug, which is quite subtle.
If I create a mixer playlist with say two or three rules it works fine, with either play sequential or random radio buttons selected.
If I edit the criteria - perhaps changing the number of items to be selected or within criteria say changing the genre for a selection, click update and or save this also works fine.However, if I take that playlist, click edit and then add a new rule of any type, update save and close, the new rule is Not implemented in the output. But if I quit out of Music Bee and then re-open it, then the rule is applied and works.
This I can repeat many times and is actually why I didn't understand how mixers worked in the beginning, because I was trying things out and couldn't see any changes (and at that point didn't think to quit the program).
I am on 3.5.8249 and waiting by my bucket in case