X5 2004 tranny top up

[Wookie_79]

That’s what i thought to do temporarily because there is a small leak from mechatronics connector, read somewhere its a common issue when not replaced along with the filter, apparently o-rings go bad.
So:
1) if i just want to top up, get it to 30* and top up BUT how do i know what fluid to add? Will any Dextron III do?

2)if replace & fix the leak i can add any compatible ATF i choose. Most guys recommend redoil or Castrol trans max. Or should i go for ZF own ATF oil?

Thanks!