I installed the lightbox on my form and called it from my existing program. Same result (with the form dropping about 12 or so pixels) in the same GDI+ call but in your lightbox image object. I called the ShowLightBox method directly.

Thisform.LightBox.ShowLightBox(oBrowser,mLeftOffset, mTopOffset, mWidth, mHeight)

and changed your code to:

Lparameters oBrowser, mLeft, mTop, mWidth, mHeight
Thisform.LockScreen = .T.
Local loCaptureBmp As xfcBitmap

With _Screen.System.Drawing
  loCaptureBmp = .Bitmap.FromScreen(;
    Thisform.HWnd, ;
    mLeftOffset, ;
    mTopOffset, ;
    mWidth, ;
    mHeight )
  *
  * Write file directly to image object
  oBrowser.Parent.Parent.imgDummy.PictureVal= loCaptureBmp.GetPictureValFromHbitmap()
Endwith

Thisform.LockScreen = .F.

I do thank you for taking the time to help me with this.