using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;
using System.ComponentModel;
using System.Data;
using
Try using the SetForegroundWindow Win32 API call, instead of ShowWindow, to activate the game window. (Signature from pinvoke.net.)
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool SetForegroundWindow(IntPtr hWnd);
static void Main(string[] args)
{
Process[] processes = Process.GetProcessesByName("game");
Process game1 = processes[0];
IntPtr p = game1.MainWindowHandle;
SetForegroundWindow(p);
SendKeys.SendWait("{DOWN}");
Thread.Sleep(1000);
SendKeys.SendWait("{DOWN}");
}