I understand that you are looking for the option to have the password prompted when you access the SlingPlayer. The option that you are asking about is available in watch.slingbox.com. We would reccommend that you use the Web browser to watch the SlingPlayer on all the computers that you use. We no longer support the 2.0 SlingPlayer and we have upgraded to the Web browser. I hope that this clears up any confusion that you have.
Hope this helps,
Sling Moderation Team