Explanation
The Config.xlsx file is a configuration file that stores the values of various parameters used in the automation process1. It has three sheets: Settings, Constants, and Assets2. The Settings sheet contains hard-coded values that may need to be changed occasionally, such as file paths, file names, timeout values, etc23. The Constants sheet contains values that are universal variables for the process, such as selectors, URLs, etc23. The Assets sheet contains the names of Orchestrator Assets that are used to store dynamic values that can be accessed across different processes, such as credentials, text, boolean, integer, etc24. However, the Assets sheet does not contain the names of Credential Assets stored in Orchestrator, because they are retrieved using a different activity (Get Credentials) than other assets (Get Asset). Therefore, the Credential Assets are stored in the Settings sheet instead of the Assets sheet.
References: Config.xlsx documentation, Settings, Constants and Assets sheet in config file, Config Dictionary in ReFramework without Excel, Custom Configuration File Reader, [UiPath Framework - Assets VS Settings Sheet of Config.xlsx].

Explanation
To calculate the total number of boxes in all shipment containers, the expression that should be used is:
Convert.ToInt32(ShipmentContainers) * Convert.ToInt32(BoxesPerContainer) This expression converts the two strings, "ShipmentContainers" and "BoxesPerContainer", into integer values using the Convert.ToInt32 method. This method converts the specified string representation of a 32-bit signed integer to an equivalent integer value1. Then, the expression multiplies the two integer values to obtain the total number of boxes. For example, if "ShipmentContainers" is "5" and "BoxesPerContainer" is "10", then the expression will return 50 as the total number of boxes.
References: Convert.ToInt32 Method from UiPath documentation.

Explanation
The values to select from the drop-down lists for the in_Username and Out_UserID arguments are:
in_Username: CurrentRow("Username").ToString
Out_UserID: UserID
These values will ensure that the in_Username argument receives the value of the Username column from the current row of the dt_Users datatable, and the Out_UserID argument returns the value of the UserID variable that is generated by the GenerateUserID.xaml workflow.

Explanation
The Anchor Base activity is used to automate interaction with an application when the element selector is not reliable and the element's position on the screen changes. The Anchor Base activity consists of two parts: an anchor and an action. The anchor is a UI element that has a reliable selector and a fixed position relative to the target element. The action is the activity that performs the desired operation on the target element. The Anchor Base activity uses the anchor to locate the target element based on its relative position (left, right, top, bottom) and then executes the action on it. This way, the automation can handle dynamic and complex UI elements that have unreliable selectors or change their position on the screen. References: Anchor Base and Example for Anchor Base Activity from UiPath documentation and forum.

Explanation
The Get Text activity is used to extract the text value of a specified UI element. It does not use any of the scraping methods by default, but it can be configured to use the Full Text method in the Properties panel. The Full Text method is able to capture hidden text from an application, as well as the entire visible text and editable text. The Full Text method uses an internal OCR engine that works with most applications and languages.
References:
Get Text activity documentation from UiPath
Screen Scraping Methods documentation from UiPath
Text scrapping forum post from UiPath Community
How to: Scrape the Whole Text, Including Hidden Elements from a Terminal Window article from UiPath Knowledge Base