The KampData TaxEngine can calculate tax without a Customer ID.
Customer IDs are only required if you are saving documents in the KampData TaxEngine transaction history for use with the KampData TaxEngine sales tax reports.
The Customer ID is also required if you have certain customers who are exempt from sales tax and you want the KampData TaxEngine to automatically utilize that exemption.
By setting the DocCustomerID property, the KampData TaxEngine can determine if that customer has been setup as taxable or exempt in the DZ Customer Supplement window. The LineState property is used to handle customers who are taxable in some states and tax exempt in other states