Thanks! Will try to answer them all:
1. Yeah, I combined them all into regional 'Lower Leagues' to make it easier to add all teams to the ANZAC Cup. The editor gets super slow when trying to add multiple competitions. I'll see if I can find some time to add promotion/relegation there too.
2. You're right, Broken Hill is in NSW. However, it's closer to Adelaide than Sydney so I figured it was more suitable for them.
3 & 4. I think this is a symptom of me updating the database for each save. I first created this is 2022, then updated it to work with FM23 and now 24. Along the way, it seems like clubs have merged and been added to the game but my edit duplicates them. I haven't confirmed it yet but it's a theory.
5. Not sure here? There's only one GC United in my database.
6. To be honest, not sure here either. I don't think the NZ teams can qualify for Asia. I tried to make that happen once but it got messy.
Re: the teams falling into the wrong divisions, I think I've got a fix but just doing some testing. Thanks for the questions and feedback!