Fake, clamped cursor in WebBuild

I'm making a gesture heavy game (simple but "broad" gestures). As a result I want to clamp the mouse to the game window so that errant gestures don't end up switching you away from the game. It's working out okay so far, but now I need to make a web build.

I've been using Screen.lockCursor = true; and Screen.hideCursor in various places (OnApplicationFocus(), Start(), OnMouseClick() etc.), then I've set up a fake Screen-space cursor to move using Input.GetAxisRaw("Mouse X") and Input.GetAxisRaw("Mouse Y").

This seems to work in standalones and in the editor.

In the web player, the fake cursor only updates properly in development builds, and not in full release.

Also, the cursor doesn't actually get locked to the screen at all, whether I turn the locks on in Start() or OnApplicationFocus() or in OnMouseClick()

Does anyone have any experience with this? I'm using Chrome and a Mac to try this stuff in.

I tried this out in a test script and it still doesn't work (Mac OSX, Chrome, Unity 3.4.2f2). Try attaching the below to a Sphere in an empty scene. Seems to work in editor but not in web-build. If no-one else can reproduce, it could be something in my project settings, i guess? If not, I hope it gets fixed :)

using UnityEngine; using System.Collections;

public class TestMouseLock : MonoBehaviour {

 // Use this for initialization
 void Start () {
 
     //Setting the screen lock on. Pulls the cursor to the center of the screen.
     //Works in editor/standalone, but not in web build.
     Screen.lockCursor = true;
     
     transform.position = Camera.main.transform.TransformPoint( Vector3.forward * 10.0f);
 }
 
 void OnMouseClick()
 {    
     Screen.lockCursor = true;
     
 }
 
 // Update is called once per frame
 void Update () {
     transform.position += new Vector3( Input.GetAxis("Mouse X"), Input.GetAxis("Mouse Y"), 0.0f); 
 }

}