Actually, you don't need to use a hacked version anymore. You could just use
closemul. It launches the emu for you and uses whatever key or combination of 2 keys you want to close it.
Here's the way your nes.ini should look. (if you're using mamewah)
### nes.ini (mamewah v1.62) ###
emulator_title Nes
### List Generation Settings ###
rom_path C:\juegos\Nes\roms
rom_extension zip
dat_file auto:[emuexepath]\[emuexename].dat
nms_file
catver_ini_file auto:[emuexepath]\catver.ini
list_generation_method rom_folder
### Execution Settings ###
pre_emulator_app_commandlines
emulator_commandline C:\juegos\nes\closemul.exe "[rompath]\[name].[romext]"{nodosbox}{safelaunch}
post_emulator_app_commandlines
general_app_commandlines
### Artwork Settings ###
artwork_image_paths C:\juegos\Nes\snaps;
movie_preview_path C:\juegos\Nes\videos
movie_artwork_no 1
enable_fuzzy_search 0
history_dat_file auto
history_dat_artwork_no 2
### Screen-Saver Settings ###
enable_music_in_screensaver 1
select_random_game 0
saver_type gamelist_slideshow
movie_path
movie_fullscreen 1
quit_delay 0
saver_commandline
### Additional Settings ###
music_path
lcd_display_file_path
description_display [description]{scroll}
### Settings used by MAMEWAH ###
current_list 0
If you're interested. I've attached closemul ready to use. Just unzip it to the same folder as FCEultra and modify your ini to point to closemul.