The Mégane II Owners' Club

Hiya I'm having issues with my mk 2 cab auto box I think it needs an oil change anyone know how many litres it takes and is it filled via the double drain plug method as there' looks to be a filler on top with a star key fitting but worried in case it's not the right one and I knackers gearbox
It's a 2003 cabriolet
Many thanks any advice very welcome
Marc