CAN AN EXCEL XLSM FILE READ FROM A CSV AND WRITE BACK TO THE SAME XLSM -VBA

Question

Hey Carlos- Here's the repost. 
Could an XLSM file read a line from a CSV file in "A1" and depending on what was in the first column in the XLSM, search the CSV file and find the indexed item in the second column or third? I've done it before with standard VLookup functions and it was cumbersome and very slow, and for some reason, everytime I would save the file it would take forever although the xls file was a single sheet.
i've attacthed a sketch of what I'm talking about, because it's hard to explain and I think the sketch explains it better. Here it is, sorry if it is blurry, it looked fine before I posted:

Answer 1

ok, use this version, I changed it a bit. To accommodate the issue with the single cell, I moved the main procedures to a function for a more efficient use.
Sub xlsmCsvLookup()
    'have both your xlsm and your csv files open
    'in the xlsm file, select a range of cells to look up
    'run the script to search all selected cells and get the values from the csv file
    Dim csvDataRange As Range 'csv file data column
    Dim selRange As Range 'to hold selected cells
    Dim foundRange As Range
    'get the source range
    Set csvDataRange = Workbooks("Book2.csv").Sheets(1).Range("a:a") ' replace "Book2" with yourCSVfile.csv
    'check for selection, only one cell, ceck that cell and exit, otherwise loop thru selection
    If Selection.Count > 1 Then
        'loop thru all selected cells, ignore empty cells
        For Each selRange In Selection.SpecialCells(xlCellTypeConstants)
            findSelection selRange, csvDataRange
        Next
    Else
        findSelection ActiveCell, csvDataRange
    End If
    Set foundRange = Nothing
    Set selRange = Nothing
    Set csvDataRange = Nothing
End Sub
Function findSelection(selRange, csvDataRange)
        'try to find it in the csv file
        Set foundRange = csvDataRange.Find(selRange) 'if found, assign it to foundRange
        'if no match highligh cut
        If foundRange Is Nothing Then
            selRange.Interior.ColorIndex = 34
        Else
            'if found, get the value in next cell
            selRange.Offset(0, 1) = foundRange.Offset(0, 1)
        End If
End Function