I have a question about the radial force actor: let’s suppose I have a radial force actor that pulls actors towards it, and I’ve got a bunch of cube actors, as well as sphere actors in my scene. Is it possible for one to pick only specific actors that are pulled towards the radial force actor (for example, only the cubes)? Thanks!
You can create a custom object channel for the objects that you want pulled then, in your radial force component, set the object types affected to this. Conversely, you can create a custom object channel for the objects you don’t want to affect and leave that one off the list.
Got it working; thanks 
A bit related question:
Can i create/use custom object channel to exclude some physical bodies from colliding with another class of objects?
I need my bullet projectiles ignore collision of player pawn. Now spaceship (pawn) is able to shoot self, when it does that projectiles randomly spin spaceship.
Also projectiles are physics based and with mass comparable to spaceship, they need to have some visible punch on everything but players spaceship.
Because game is for mobiles i rather not add timer to each bullet that turns on physics after split of second, also no matter of spawn offset from spaceship it is possible to catch up bullet, so i need some general solution to exclude collision of player pawn from colliding with projectiles.
PS.
I will experiment with those custom channels today.
I can’t see to get my custom physics body working properly with radial force. I create a new Object Channel called Effects and set the default response to Block. Then I created a preset for it and set it to ignore all but World Static and World Dynamic and set its collision to Query and Physics.
When I set my static meshes to use the new Effects channel, they still simulate physics, but when I set the radial force to affect Effects, they don’t move when I fire the impulse. As soon as I switch their collision back to PhysicsActor, it works. Any ideas?