Js to c# conversion

I'm trying to convert an old camera script from JS to C# but I'm duing something wrong as the camera behaves very strange. Anyone that can help me fix it?

The scripts can be tested by attach it to a Camera and setting the target transfrom to a sphere or something like that (it will be used as a rotation point).

The JS version:

 // Attach this to a Camera and it will be controlled using the following input
 //
 // W: Move camera forward
 // S: Move camera backwards
 // A: Strafe camera to the left
 // D: Strafe camera to the right
 //
 // Mouse scroll wheel: Zoom in and out
 //
 // While pressing Shift and moving the mouse: rotate and pan the camera around the target
 
 var target : Transform; // Is used as a rotation point
 var distance = 25;
 
 var xSpeed = 450.0;
 var ySpeed = 220.0;
 
 var yMinLimit = 30;
 var yMaxLimit = 89;
 
 private var x = 0.0;
 private var y = 0.0;
 
 var maxDist : float = 50;
 var minDist : float = 5;
 var zoomSpeed : float = 2;
 
 var speed : float = 50.0;
 var modifier : float=1.0;
 
 // Add this script so that it can be accessed from the Unity3d editor
 // It will be under the Component menu
 @AddComponentMenu("Camera-Control/Mouse Orbit")
 partial class MouseOrbit { }
 
 function Start () 
 {
     var angles = transform.eulerAngles;
     x = angles.y;
     y = angles.x;
 
     // Make the rigid body not change rotation
     if (rigidbody)
         rigidbody.freezeRotation = true;
 }
 
 function LateUpdate () 
 {
     if (target) 
     {
         
         // Mouse pan
         if(Input.GetKey (KeyCode.LeftShift))
         {
             x += Input.GetAxis("Mouse X") * xSpeed * 0.02;
             y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02;
         }
 
         y = ClampAngle(y, yMinLimit, yMaxLimit);
         
         // Update target rotation
         target.rotation = Quaternion.Euler(0.0, x, 0.0) ;
         
         // Update camera target position
         // Move forward and backward 
         var forward = target.forward * modifier * Time.deltaTime * speed * Input.GetAxis("Vertical");
         target.position+=forward;
         
         // Strafe right and left
         var right = target.right * modifier * Time.deltaTime * speed * Input.GetAxis("Horizontal");
         target.position+=right;
         
         //var up = Vector3.up * modifier * Time.deltaTime * speed;
         //target.position+=up;
         
         // Zoom in and out
         if (Input.GetAxis("Mouse ScrollWheel") < 0 && distance < maxDist)
         {
             distance += zoomSpeed;                             
             transform.Translate(Vector3.forward * -zoomSpeed); 
         }
         else if (Input.GetAxis("Mouse ScrollWheel") > 0 && distance > minDist)
         {
             distance -= zoomSpeed;                             
             transform.Translate(Vector3.forward * zoomSpeed); 
         }    
         
         // Restrict the target y position to the height of the terrain at the current target position
         target.position.y  = Terrain.activeTerrain.SampleHeight(target.position) + 1;
     
         // Update camera position    
         var rotation = Quaternion.Euler(y, x, 0);
         var position = rotation * Vector3(0.0, 0.0, -distance) + target.position;
 
         transform.rotation = rotation;
         transform.position = position;
         
         // Restrict the camera y position to the height of the terrain at the current camera position if the camera would be under the ground
         if(transform.position.y <= Terrain.activeTerrain.SampleHeight(transform.position) + 5)
             transform.position.y  = Terrain.activeTerrain.SampleHeight(transform.position) + 5;
     }
 }
 
 // Make sure the angle dosn't excede 0 - 360 degrees
 static function ClampAngle (angle : float, min : float, max : float) 
 {
     if (angle < -360)
         angle += 360;
     if (angle > 360)
         angle -= 360;
     return Mathf.Clamp (angle, min, max);
 }

The C# version (that dont't work):

 using UnityEngine;
 using System.Collections;
 
 // Add this script so that it can be accessed from the Unity3d editor
 // It will be under the Component menu
 [AddComponentMenu("Transform/Follow Transform")]
 public class MouseOrbit : MonoBehaviour 
 {
     // Attach this to a Camera and it will be controlled using the following input
     //
     // W: Move camera forward
     // S: Move camera backwards
     // A: Strafe camera to the left
     // D: Strafe camera to the right
     //
     // Mouse scroll wheel: Zoom in and out
     //
     // While pressing Shift and moving the mouse: rotate and pan the camera around the target
     
     public Transform target; // Is used as a rotation point
     public float distance= 25f;
     
     public float xSpeed= 450.0f;
     public float ySpeed= 220.0f;
     
     public float yMinLimit= 30;
     public float yMaxLimit= 89;
     
     private float x= 0.0f;
     private float y= 0.0f;
     
     public float maxDist = 20;
     public float minDist = 5;
     public float zoomSpeed = 2;
     
     public float speed = 50.0f;
     public float modifier = 1.0f;
     
     void Start ()
     {
         Vector3 angles= transform.eulerAngles;
         x = angles.y;
         y = angles.x;
     
         // Make the rigid body not change rotation
         if (rigidbody)
             rigidbody.freezeRotation = true;
     }
     
     void LateUpdate()
     {
         if (target) 
         {
             // Mouse pan
             if(Input.GetKey (KeyCode.LeftShift))
             {
                 x += Input.GetAxis("Mouse X") * xSpeed * 0.02f;
                 y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02f;
             }
     
             y = ClampAngle(y, yMinLimit, yMaxLimit);
             
             // Update target rotation
             target.rotation = Quaternion.Euler(0.0f, x, 0.0f) ;
             
             // Update camera target position
             // Move forward and backward 
             Vector3 forward = target.forward * modifier * Time.deltaTime * speed * Input.GetAxis("Vertical");
             target.position += forward;
             
             // Strafe right and left
             Vector3 right = target.right * modifier * Time.deltaTime * speed * Input.GetAxis("Horizontal");
             target.position += right;
             
             //FIXME_VAR_TYPE up= Vector3.up * modifier * Time.deltaTime * speed;
             //target.position+=up;
             
             // Zoom in and out
             if (Input.GetAxis("Mouse ScrollWheel") < 0 && distance < maxDist)
             {
                 distance += zoomSpeed;                             
                 transform.Translate(Vector3.forward * -zoomSpeed); 
             }
             else if (Input.GetAxis("Mouse ScrollWheel") > 0 && distance > minDist)
             {
                 distance -= zoomSpeed;                             
                 transform.Translate(Vector3.forward * zoomSpeed); 
             }    
             
             // Restrict the target y position to the height of the terrain at the current target position
             Vector3 pos = target.position;
             
             pos.y = Terrain.activeTerrain.SampleHeight(target.position) + 1;
             target.position = pos;
         
             // Update camera position    
             Quaternion rotation = Quaternion.Euler(y, x, 0);
             
             Vector3 position = rotation * (new Vector3(0.0f, 0.0f, -distance) + target.position);
             
             transform.rotation = rotation;
             transform.position = position;
             
             // Restrict the camera y position to the height of the terrain at the current camera position if the camera would be under the ground
             pos = target.position;
             if(pos.y <= Terrain.activeTerrain.SampleHeight(transform.position) + 5)
                 pos.y  = Terrain.activeTerrain.SampleHeight(transform.position) + 5;
             
             target.position = pos;
         }
     }
     
 
     //public static Vector3 r operator +(Vector3 a, Vector3 a)
     //{
 //           return new Vector3(a.x + b.x, a.y + b.y, a.z + b.z);
 //    } 
 
     
     // Make sure the angle dosn't excede 0 - 360 degrees
     static float ClampAngle (float angle, float min, float max)
     {
         if (angle < -360)
             angle += 360;
         
         if (angle > 360)
             angle -= 360;
         
         return Mathf.Clamp (angle, min, max);
     }
 }