Вопрос: Как добавить пункт к системному меню, находящемуся рядом с названием окна?

Ответ :

Примерно так 

code:
--------------------------------------------------------------------------------

//h-file
...
    void __fastcall OnSysCommand(TWMSysCommand&);
public:         // User declarations
    __fastcall TForm1(TComponent* Owner);

    BEGIN_MESSAGE_MAP
        MESSAGE_HANDLER(WM_SYSCOMMAND, TWMSysCommand, OnSysCommand);
    END_MESSAGE_MAP(TForm)

....


/cpp-file

static const SC_MY_MENU_ITEM = WM_USER + 1;

void __fastcall TForm1::FormCreate( TObject *Sender )
{
    AppendMenu( GetSystemMenu( Handle, FALSE ), MF_SEPARATOR, 0, "" );
    AppendMenu( GetSystemMenu( Handle, FALSE ),
                MF_STRING,
                SC_MY_MENU_ITEM,
                "My Menu Item" );
}
//---------------------------------------------------------------------------

void __fastcall TForm1::OnSysCommand(TWMSysCommand& msg)
{
    if(msg.CmdType == SC_MY_MENU_ITEM){
        ShowMessage("It's my point!!!");
    }else
        TForm:: Dispatch(&msg);
}
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