@ houseparty.. I dont own Mortal Kombat 4 but i do have a few games from the sold out range (colin mcray rally 2, theif ect) and what i have found is when i back up my sold out games i do not need a nocd crack to run them, All i seem to need is the backed up disk so my guess is the protection being used is "cd check" wich just needs the backed up cd in the drive

and no crack or fixed exe is needed. However when the games are new(ish) and not in the sold out range then obviously they may need a crack Hope this info helps
Also did you even look in game copy world for what you requested?? I just HAVE and mortal combat 4 crack is here
http://gamecopyworld.com/ and so far i have never D/L a no-cd crack from game copy world that dosent work, Thats not to say there not out there though

. You said "you have tried loads of different cracks but none work so you might be doing it wrong" Have you used a no-cd crack that works in the past?
What i mean is are you doing it correctly? (i will explain what to do as though you dont have a clue) The normal method for a no-cd crack is this = D/L no-cd crack but make sure its the same version of the game your running, Install the game (maximum install) then after install go into the game directory (double click the "my computer icon on the desk top for win 98, or use the start button and acess "my computer" for different versions of windows,(im unsure wich one is done like that but i think its XP) Once inside "my computer" go into your hard drive (default is normaly C

RIVE unless you have changed it) Once inside your c:drive go inside "program files" and then look for the folder the game is in. (this can have the manufactours name on the folder or the name of game ect) Once inside the game folder find the original exe (thats the same picture as the shortcut for the game on the desk top,providing you choose to have a short cut) Once your in here minimize the window and go to where ever you saved the no-cd crack and unzip it to your desk top(make sure you make a folder for it on your desk top for it to in as it can promt you to overwrite your short cut on the desk top) once unzipped and in the folder you just made right click on the no-cd crack (same pic as the original exe and short cut on the desk top normaly) and select copy. Then close this window down after you have selectd the copy option from the drop down menu and re-open the game folder from the task bar at the bottom of the screen and right click some where in here where it is blank and select the paste option from the drop down menu. You will be prompted to overwrite or cancel this opperation and simply choose the overwrite option and thats it m8. There are other ways of doing a no-cd crack but this one in my opion is easy for beginers. hope this info helps you out, it bloody better cause it took long enough to type