In order for Spectrum to import orders for manufacturing, there must be an indication that the line item is a customized item versus a stock item. The preferred method to do this is to create a custom line item property called "Recipe" (Note: name is configurable) to store the recipe identifier that is passed to Shopify via the process. This allows Spectrum to seamlessly .
Relatedly, if following the product set up guidance, where the customization "add-on"/upcharge is configured as a unique variant, Spectrum recommends a line item property to associate the "add-on" with a line item. The recommended line item property name is "RelatedRecipe" (Note: name is configurable). The benefit to setting this property is that it allows Spectrum to fulfill all custom line items associated with the order automatically.