This server behavior is used to setup the order VAT. To give you the max flexibility you must create the recordset with the standard Dreamweaver recordset behavior so you can define the recordset filter like you need, besed on the user account or others methods.
Recordset:
The recordset name where get the VAT setup
Value field:
The recordset field where find the VAT percentage
Decimal round:
The number of decimal you need have for the VAT amount