Which berries are in season in NZ now? Which bird(s)? How are you cooking them?
There are a few basic approaches to berry sauces for game. One is to dissolve preserves in something acidic (balsamic vinegar, or a red wine, to name a couple), then add some fresh berries and warm til heated through. This method is especially good as a pan reduction made with some of the cooking fond.
The other is to make a reduction of chicken and beef stocks and port, then add tart, aromatic berries -- like juniper berries. This is a classic, stand alone sauce.
Speaking of classics, you may want to try a play on Cumberland sauce, using blackcurrants and blackcurrant jelly instead of the red currant jelly which is standard. I mention this because blackcurrants were the first berry I could think of that are commercially farmed in NZ.
I'm not sure how I feel about chocolate and fresh fruit for game. If I were using chocolate with meat, I'd unite the two with something like cinnamon, chile, nuts or even dried fruit. Off hand, fresh fruit seems like it would be pressing dessert buttons too hard. The whole chocolate thing sounds kind of like a Oaxacan black mole (mo-lay) which is a wonderful thing but a heck of a lot of work and calls for a boatload of ingredients unavailable in your hemisphere. Otherwise ...
The more specific you are, the more specific I can be.