in a simple answer with costs in AUD and sales in USD a...

in a simple answer with costs in AUD and sales in USD a depreciating AUD is better for the bottom line

but Im pretty sure this operation has been loss making for some time so from memory Ansteel or whoever the JV partner is has first right of cost recovery from any sales and profits which make take some time to clear?

GBG is basically a cash box with a residual investment in Karara, they should sell their remaining interest and perhaps return those proceeds to long suffering shareholders in the form of a capital return or dividend
Im sure the Chinese would rather own Karara outright anyway and the company seems pretty keen to look at something new so why not just dispose of the investment all together