Produmex Scan - Customization

Does someone know what this functions in customization do:

• DataRepeater_ExternalScreenLoad
• DataRepeater_InternalDataLoad
• ExternalScreenLoad

I try to copy quantity from StocInfoScreen to TransferStocksQuantitiesNormalScreen ($[SelectedBinLocationStockForTransfer.OnHandQuantity] ) in [TextQuantity] but it doesnt work. Tried _Load but it doesn't work from StockInfoScreen.