Text Tutorial:
1.) Open Notepad and past this
@echo off
start %installdir%iw4m.dat
2.) Click "Save As"
3.) change "Save As Type" to "All Files"
4.) Name the file whatever you want but include ".bat" to the end.
5.) Seriously make sure ".bat" is at the end of the name.
6.) Past file into your IW4 Directory.
7.) Launch it and enjoy!