I read this as three parts:
1 BoB yada yada
2 US built in RAF service, German built in Croatian service, etc. NOT captured unless put into service.
3 Aircraft in service with "minor" countries like Greece, Holland, Finland etc. This is to get us away from the usual German, British and US subjects.
Yes all WW2.
Geez I'm still working on my Aces GB subject. I don't have any BoB stuff in the stash anymore so may throw in a Avia B534 or a Finnish Gladiator. I also have a Mitchell I could do in RAF marks but I don't want to do another twin for a while.