I have just installed v188.8.131.52 and have followed the precise settings outlined to setup for an Australian company (at the fontis.com.au site). It appears that the GST is NOT calculating correcty in either the shopping cart or checkout.
For example i have created a test item that costs $110.00. Once selected is displays in the Shopping Cart as follows:
Test 100.10 1 $100.10
Grand Total $100.10
Anyone heard whether anything is wrong with this release of Magento???