thanks progets, when I read your first reply I didn't process it well, and went to the link which didn't help. Problem was that I was so used to using a different romlist for each display, it took a while to realise I could share the romlist. I actually worked it out myself while I was away, but if I hadn't you would have saved me
I also got rid of the 'good' tag and went back to using favourites instead of tags (no need for user to see list of tags)
also discovered that tags can't start with a number in v2.0.0
here's mine:
display DefenderPlus8way
layout basic_panels_DefenderPlus8way
romlist mame_defenderplus842way
in_cycle yes
in_menu yes
global_filter
rule FileIsAvailable equals 1
filter Faves_842way
rule Favourite equals 1
filter Defenders
rule Tags contains defender
filter Faves_82way
rule Favourite equals 1
rule Tags not_contains z4way
filter The_Rest_8way
rule Favourite not_equals 1
rule Tags not_contains defender
display DefenderPlus4way
layout basic_panels_DefenderPlus4way
romlist mame_defenderplus842way
in_cycle yes
in_menu yes
global_filter
rule FileIsAvailable equals 1
rule Tags contains z42way
filter Faves_42way
rule Favourite equals 1
filter Defenders
rule Tags contains defender
filter The_Rest_4way
rule Favourite not_equals 1
rule Tags not_contains defender
here's the panel if anyone's interested