Sub Macro1()
Dim LastRow As Long, DateStart As Date, DateFinish As Date
Dim Rng As Range, j As Long, DifDays As Long, i As Long
Dim Shag As Long, x As Long, ColStart As Long, LastColumn As Long
    LastRow = Cells(Rows.Count, 1).End(xlUp).Row
    LastColumn = Cells(3, Columns.Count).End(xlToLeft).Column
    Shag = Cells(2, 7)
    For i = 4 To LastRow
        If Cells(i, 2) <> "" Then
            DateStart = Cells(i, 4)
            DateFinish = Cells(i, 5)
            DifDays = DateFinish - DateStart
            Set Rng = Range(Cells(3, 8), Cells(3, LastColumn)).Find(what:=DateStart, LookIn:=xlValues, LookAt:=xlWhole)
            If Not Rng Is Nothing Then
                ColStart = Rng.Column
                For j = ColStart To ColStart + DifDays
                    Cells(i, j) = x + Shag
                    x = x + Shag
                Next
            End If
        End If
        x = 0
    Next
End Sub