Always make a backup of the files that are overwritten by the File Archive, as the original files are usually required to update the game to a newer version or to play Online!
Some original games do not work when a certain application is installed, like DAEMON Tools. In most cases using a No-CD or Fixed EXE will solve this problem!
Some Game Trainers are sometimes reported to be a Virus or Trojan, in most cases a keylogger called HotKeysHook but in ALL cases this is a false alarm as NONE of the Game Trainers @ GCW contain malicious code! More info in the PC Games FAQ!
If you have problems using a trainer in combination with Windows Vista then make sure to run the trainer with Administrator rights and when needed in Windows XP or Windows 98 compatibility mode!