A product on sale has two prices: the one the customer pays today and the was price, the one shown crossed out. It seems like a detail until a tool keeps only one of them. If it keeps the was price, your catalog shows prices nobody charges. If it keeps today's price and publishes it as the regular price, the sale disappears from the store. Either way, someone gets a nasty surprise.
Two prices, each in its place
In Noobit, every product record keeps both, each with a clear name:
The same goes for each variation of a variable product: each size or color has its price and, if it's on sale, its was price.
From your store to your catalog
When a price comes in from WooCommerce, what the store actually charges is what counts. If a sale is running, the sale price becomes the price and the regular price becomes the was price. If a sale is scheduled but hasn't started yet, it isn't a sale yet: the price is the regular one. Changes made in the store come in right away, and you can import prices manually whenever you want.
It works the same way with a CSV: if you bring in a price column and a sale price column, and the sale price is lower, it's today's price and the other one becomes the was price. If you only bring in the price, there's no sale.
From your catalog to your store
When you publish prices, the product record has the final say and sends both together. If there's a was price, the store gets the regular price and the sale price; if there isn't, it gets the price and an empty sale price, which removes any sale that was there. That way, what you see in Noobit is what the store charges, with no old sales still running because nobody took them down.
And the barcode, in its own field
Since version 9.2, WooCommerce has its own field for the GTIN or EAN, the one you see and correct in your store's admin. Noobit reads it and writes it: on the way in, if that field has a value, it takes priority over the one your EAN plugin stores. When publishing, both are sent, and if the store rejects its own — because it's a duplicate or badly formatted — the product is published anyway, without that field.