How do you set up kitchen / hospitality printer functionality within RetailVista?

First, product groups need to be created, one per kitchen printer. 

Go to Administration > Product Groups and choose to add.
Enter the code of the kitchen printer to which the products in this product group should be printed. Using a code of 9 will print a product to all kitchen printers. This is especially useful for adding a table or buzzer number as a product to a transaction. That 'Product' will then be printed as an addition to the receipt in all kitchens (provided there is an order for the respective kitchen department, so if no sandwiches are ordered, for example, no receipt will come from the 'Sandwich printer' with/from product group 9)

For a 2nd, 3rd, and 4th kitchen printer, respectively, codes 2, 3, and 4 should be used.

Now the kitchen printer needs to be configured in the respective POS terminal.
Go to Administration > POS terminals and select the relevant POS terminal.

Add the receipt printer on the "Extra printers" tab to which the printing should be directed.

This is only about the receipt printer configuration, later a Windows printer still needs to be selected on the POS terminal itself. If the same type of receipt printer is used as the rest of the POS terminals, the receipt printer that is already configured on the "POS terminal" tab can be chosen here.

Standard kitchen printer where the normal receipt is printed.

Kitchen printer 1product in the product group with code 1
Kitchen printer 2product in the product group with code 2
Kitchen printer 3product in the product group with code 3
Kitchen printer 4product in the product group with code 4

Copy kitchen printer where a copy of the normal receipt is printed.

Now the product groups must be assigned to the correct products. Search for the relevant product and enter one of the previously created product groups in the product group field.

The product must also be marked as a kitchen product. This can be done on the "Sales" tab of the product.

This ensures that the product is printed on the correct receipt/kitchen printer and that a window appears on the POS terminal when the product is entered, allowing for entering comments regarding the product, for example 'No salt' or 'Extra well-done'.

These comments can be typed in or a pre-set comment can be selected.
The kitchen comments can be created via Administration > Kitchen comments.

Finally, the POS terminal must specify which Windows printer should be used.
This can be set on the respective POS terminal via Management > Configuration > Printers.

When, for example, an omelette and a glass of milk are entered in the restaurant, a receipt with 'Omelette, broken yolks, brown bread, no salt' can be printed from the printer near the stove...and at the bar, a receipt with 'Glass of milk' can be printed.
Additionally, a control receipt can be printed from the order printer, containing the entire order, so that the total receipt can be checked again when serving.

Finally, under Extra -> Settings -> GUI, set the field 'Comment 1 to 4 after each hospitality product' to 'Yes'.