Diminishing shade in a photo

[hvw]

Make a selection of the shaded area and run following macro:

Dim X As Long
Dim Y As Long
Dim H As Long
Sub Schaduw()
Set Doc = ActiveDocument
Doc.Mask.Feather 4, pntFeatherInside, pntEdgeLinear
Application.CorelScript.EditCopy
X = Doc.Mask.PositionX
Y = Doc.Mask.PositionY
H = Doc.Mask.SizeHeight
Application.CorelScript.EditPasteObject
Set Laag = Doc.ActiveLayer
Laag.Move X, Y + H
With PHOTOPAINT.CorelScript
.BitmapEffect "Desaturate", "DesaturateEffect"
.BitmapEffect "Gaussian Blur", "GaussianBlurEffect GaussianBlurRadius=600"
.BitmapEffect "Invert", "inverteffect"
End With
ActiveLayer.MergeMode = pntMergeOverlay
Set Laag = Doc.ActiveLayer
Laag.Opacity = 50
Doc.Layers.Merge
Doc.Mask.Delete
End Sub

With help of Shelbym