I am using a raycast to destroy objects when they are close enough. The script works on objects such as a cube, capsule, ect. but not on say an imported game character. What could possible cause this? Remember the script DOES work on objects that are not imported, Its just the ray does not detect imported objects.
Thats really simple all you have to do is add a collider to the mesh you can either do it manually by clicking generate colliders at asset importer or go component>Physics>MeshColldier(i dont recommend using this as it slow down game instead use box or cylinder colldier to create a basic shape)
Are you sure the ray is actually hitting the object collider?
Maybe try Collider.Raycast?
Physics.Raycast casts a ray against all Colliders in a scene (http://docs.unity3d.com/Documentation/ScriptReference/Physics.Raycast.html).
Have you ensured that your imported game characters have Colliders on them?