You’ve landed on a major limit with the 3d in construct. Collisions (including with the mouse) only happen in 2d on the z=0 plane.
Seems it’s basically a problem of calculating if a ray from the camera to the mouse position is intersecting the sprite’s quad. Just a bunch of math since construct doesn’t have anything that helps with that. But you could try searching the forum for 3d ray cast for various possible solutions.
If an object doesn’t have the spawn action just use the system->create action.