To successfully swap models without the game crashing, follow these general steps found on the Resident Evil Modding Boards :
If the game crashes when you Alt+Tab to use the trainer, try running the game in Windowed Mode Are you planning to use these swaps for a co-op session , or are you primarily looking for single-player modifications? patch v1 4 1 for re5 model swap trainer link
Open the "Prerequisite" folder and copy all contents into your RE5 installation directory (usually \SteamLibrary\steamapps\common\Resident Evil 5 ). Apply any "Crash Fix" files included in the patch folder. : Download and open the RE5 Model Swap Trainer v6.3. To successfully swap models without the game crashing,