How do I set certain objects to activate during my pause menu ?

Forgive me if you have, but have you tried the “Is Game Paused” function?

create a function/event (with all the stuff u want to activate/spawn) in the gameinstance or GM and call it from where u r creating/adding the pause menu to the viewport.

Particle system, static meshes, material world displacement, camera movement… So far, custom time dilation isn’t doing it.

Not really but what would I put after this condition?

Well I have no idea what you’re trying to do, however based on your screenshot and the wording of your question it seems that you have an actor that you want to activate when you pause the game?

The best I can offer you is a small example of what I did for a prototype game to maybe point you in the right direction.

I mapped the input to the start button of a controller which toggles the paused state by always getting the negative of IsPaused’s current value, and then passing that into a function within my HUD. It is important that if you are going to do this you make sure that execute when paused is ticked otherwise you won’t be able to unpause the game.

In the function itself I basically just set a bunch of UI elements to be either visible or hidden depending on the paused status but you could substitute those within whatever actor you want whether it’s turning on particle effects or spawning Static Meshes.

Hopefully this at least slightly helps with what you are trying to accomplish.