In the USA, where Garmin comes from, all IFR approaches are in a minimum of class E controlled airspace so there is no such thing as going in and out of controlled airspace when on an IFR approach.
It's clear that Garmin or other manufacturers are not going to do a special design just for Australia.
That's why we decided to go to the US NAS airspace system many years ago!
Now after Mangalore it just may happen.