If you are using the Steam version, you may need to downgrade your game files or find a specific trainer designed for the Steam-Integrated version of the original release.
Medieval II has a robust set of console commands, which can be accessed by pressing the ~ (tilde) key or its equivalent (e.g., ö on German keyboards, ò on Italian keyboards). Commands like add_money 40000 provide similar effects to some trainers but offer less flexibility and require repeated manual input. medieval 2 total war trainer 1.03