For players who use Playstation 4 or 5 gamepads. You need to disable steam input for the game you are playing and use ds4windows  x360CE or a similar software to have your controller work with both Lab Monster Toolkit and your game.

Also! If you play with the analog stick and not the dpad, it is STRONGLY recommended that you experiment with ds4windows x360CE and see if the game still feels ok to play when using that software. Joystick deadzones can change between steam input and ds4windows x360CE and this can affect how inputs feel in the game.

If you only intend to use the toolkit to playback recordings with a dummy in training mode, you do not need to disable steam input, and you can just have the toolkit take players 2 and 3. But if you intend to use other features like the trainer, or added input delay, joystick deadzone issues may be a dealbreaker and I would caution purchasing this product currently, as it may result in a sub par experience compared to vanilla play.