The template is not capable of reading data from bar code scanners.
There are several formulas embedded in the document. When the size of your data approaches the limits of this template (2000 products and 50,000 line items), there is a 3 to 5 second lag while inserting new line item. After a new line item is inserted, everything else works instantly. If you notice a lag, you can save a copy of the current file and start entering new orders in a new file.