Hi gloriam, 

It looks like the system is behaving correctly in this screenshot - according to this article from the ATO, the threshold means that anything underneath that amount does not accrue super, but if you pay an employee $450 or more (before tax) in a calendar month, the super will begin to calculate. The settings in that pay run indicate that the earnings have just reached the threshold, so according to the ATO guidelines the super amount works out to be $42.75, and the SGC amount is correct. 

If you want to adjust the Super amount, you can go to the green Actions button in that employee's earnings screen and select Adjust Super, and record any changes required. 

-Lucas