Thanks for taking a look, I really appreciate it. I've also added a GUI and, I know I'm being annoying but, if it is possible could you please take another look at my "final" final code
in case I've missed some sneaky bugs.
At the moment I'm happy with the speed, and, well, at least, I hope this will be useful for some others as well.

At the moment I'm happy with the speed, and, well, at least, I hope this will be useful for some others as well.
CODE:
SendMode Input ; Sets the script to use the input method for sending keystrokes.
SetWorkingDir %A_ScriptDir% ; Sets the script's working directory to where the script is located.
#SingleInstance force ; only run one instance of this script
#NoEnv ; Recommended for performance and compatibility with future AutoHotkey releases.
SetBatchLines -1 ;max performance
ListLines Off ;max performance
;SetKeyDelay, 0 ;max key hits
#MaxThreadsPerHotkey 1
; Define mappings of countries to their row ranges in sheets 1 and 2.
countryRowMappings := {}
countryRowMappings["Germany"] := {1: [4, 12], 2: [4, 18]}
countryRowMappings["Spain"] := {1: [16, 24], 2: [22, 35]}
countryRowMappings["Baguette(France)"] := {1: [28, 36], 2: [39, 52]}
F2:: ; Hotkey to start the script.
excel := ComObjActive("Excel.Application") ; Get the active Excel application.
workbookBR := getWorkbookByName(excel, "BusinessReport") ; Get the BusinessReport workbook.
workbookVA := getWorkbookByName(excel, "Verkaufsliste Autohotkey") ; Get the Verkaufsliste Autohotkey workbook.
; Check if the required workbooks are open.
If (workbookBR = "" or workbookVA = "") {
MsgBox, % "One or both of the required workbooks were not found."
return
}
; Check the header in column "O" of the BusinessReport.
worksheetBR := workbookBR.Sheets(1)
header := worksheetBR.Cells(1, 15).Value
If (header != "Bestellte Einheiten") {
MsgBox, % "The header in column 'O' of the 'BusinessReport' workbook does not match the expected 'Bestellte Einheiten'. Please check the file."
return
}
; GUI-Definition mit angepasstem Design
Gui, New
Gui, Font, s10 cBlack, Arial ; Set font and color
Gui, Color, FFFFFF ; Set background color
Gui, Add, Text, x10 y10 w300 h30 +Center, Bitte geben Sie das Land für den 'BusinessReport' ein:
Gui, Add, DropDownList, x10 y50 w300 h300 vCountryChoice, Germany|Spain|Baguette(France)
Gui, Add, Button, x10 y100 w300 h30 Default, OK
Gui, Show, w320 h150, Work Work GUI
return
ButtonOK: ; Action when the OK button is pressed.
Gui, Submit ; Get the user input from the GUI.
global country := CountryChoice ; Store the selected country.
Gui, Destroy ; Close the GUI.
; Data transfer logic based on the selected country.
For index, sheetIndex in [1, 2]
{
rowRange := countryRowMappings[country][sheetIndex]
startRow := rowRange[1]
endRow := rowRange[2]
worksheetVA := workbookVA.Sheets(sheetIndex)
CalculateSumOfOrderedUnits(excel, workbookBR.Sheets(1), worksheetVA, startRow, endRow)
}
MsgBox, % "Data transfer for " country " completed. Press F2 to continue with a new country."
return
GuiClose: ; Action when the GUI is closed.
ExitApp
getWorkbookByName(excel, nameStart) { ; Function to get a workbook by its starting name.
Loop, % excel.Workbooks.Count {
workbook := excel.Workbooks(A_Index)
If (InStr(workbook.Name, nameStart) = 1)
return workbook
}
return "" ; Return empty string if no matching workbook is found.
}
CalculateSumOfOrderedUnits(excel, worksheetBR, worksheetVA, startRow, endRow) { ; Function to calculate and transfer total units.
month := A_MM ; Get the current month as a number.
colVA := Chr(67 + month - 1) ; Determine the target column based on the month.
rowCountBR := worksheetBR.UsedRange.Rows.Count
ASINtoUnits := {}
; Collect data from BusinessReport and calculate total units.
Loop, %rowCountBR% {
rowBR := A_Index + 1
ASIN := worksheetBR.Cells(rowBR, 2).Value
SKU := worksheetBR.Cells(rowBR, 4).Value
bestellteEinheiten := worksheetBR.Cells(rowBR, 15).Value
If (!ASINtoUnits.HasKey(ASIN)) {
ASINtoUnits[ASIN] := {"FBA": 0, "Standard": 0, "HasFBA": false}
}
If (StrLen(SKU) > 0) {
If (InStr(SKU, "-FBA") and substr(SKU,-1) != "B") {
ASINtoUnits[ASIN]["FBA"] += bestellteEinheiten
ASINtoUnits[ASIN]["HasFBA"] := true
} Else If (substr(SKU,-1) != "B") {
ASINtoUnits[ASIN]["Standard"] += bestellteEinheiten
}
}
}
; Write the total units to the Verkaufsliste Autohotkey workbook.
Loop, % endRow - startRow + 1 {
rowVA := A_Index + startRow - 1
ASIN := worksheetVA.Cells(rowVA, 2).Value
If (ASINtoUnits.HasKey(ASIN)) {
totalUnits := ASINtoUnits[ASIN]["HasFBA"] ? (ASINtoUnits[ASIN]["FBA"] + ASINtoUnits[ASIN]["Standard"]) : ASINtoUnits[ASIN]["Standard"]
worksheetVA.Cells(rowVA, colVA).Value := totalUnits
} Else {
worksheetVA.Cells(rowVA, colVA).Value := 0
}
}
}
Statistics: Posted by Mindfork — Today, 17:11