Delphi: OldCreateOrder property in a form

OldCreateOrder property was absent in Delphi 3, but present in Delphi 5.
OldCreateOrder property was removed in Delphi 11.
For instance, default for the property OldCreateOrder is False in Delphi 11 Alexandria.
OldCreateOrder controls when the OnCreate and OnDestroy events are called.
With OldCreateOrder = True the OnCreate is called inside TCustomForm.Create after the DFM is loaded in a TCustomForm descendant/
With False the OnCreate is called after all inherited constructors are finished, i.e. in TCustomForm.AfterConstruction.
With OldCreateOrder = True, the FormDestroy is called inside the inherited call of Destroy.
With OldCreateOrder = False it is called before execution of any destructor.

Undeclared identifier error: SListIndexError

The SListIndexError is a constant string declared in Delphi 4 in the unit Consts.
SListIndexError since Delphi 6 is in the unit RTLConsts.
The first and the most competent method is to resort to conditional compilation directives:
{$IF CompilerVersion >= 14.0} // Delphi 6 and higher RTLConsts {$ELSE} Consts {$IFEND}
The second remedy:
The construction Error(SListIndexError, Index) may be replaced by Error('List Index out of bounds (%d)', Index)