Yeah, grdvr is right, you can use the Group Connection to fix a special camera into a special window. You can refer to this link for setting demo :
http://cqax.meibu.com/DownLoad/temporary/swf/Group_Displaying.swf

But please tell us the hardware and software you are working with, I wonder if you are working with a hybrid DVR and our NVR Client software? We want to check your problem, to make sure it is not a bug, so we need your help to give us more details.

Best Regards.