If your question is only related to how to put the form in TPanel, then it's pretty simple. You only need to call Windows.SetParent () with the handle of the newly created form.
MyNewForm := TMyNewForm.Create(Self); Windows.SetParent(MyNewForm.Handle,MyPanel.Handle);
This will also work using the TForm ParentWindow property. But it is (possible) that transparency is not processed (I briefly checked with a translucent shape, and it is not drawn correctly, therefore, if transparency is mandatory, it is impossible to achieve the goal ...)
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