How to setup a few of Taxes as VAT?

 Hi,

Does anyone know exactly how to setup tax correctly?  After I setup taxes, when I click (Button) calculate tax on Payable Invoices, only a default Tax Regime, Tax, Status and Rate is defined automatically to Tax line?

For instance, I create new tax status as Deferred VAT and any = 10%, next I define default on Tax Classification Code on Supplier and Site.  I create Payable Invoices with an item line, the Tax Classification Code is default correctly.  But tax line is generated with only a default Tax Information and Status, as well as Tax Rate different from Tax Classification Code default on item line.