I hope someone who has better knowledge of the ins and outs of .htaccess will answer this question for you, but for now, let me see if I can share what I know about .htaccess.
From my understanding, the two options you mentioned (forbid linking to files in this directory and forbidding file extensions) have to do with preventing people from HOTlinking to the various files in the protected directory.
Hotlinking in your case is people who, without membership/logging into the secured (or unsecured) area, try and access the files in the protected area.
If the page is in the secure area, from my understanding, you need to be logged into that area to see the page and to see everything else.
If you ARE logged in and you still can't see the images and links and whatnots, then it's probably your coding that is off.
Are you linking to images and videos from ANOTHER protected part of your website for example?
Are your image and link tags and anchors coded correctly?
Check up on all these possibilities and if you still have problems, post again and maybe someone else who has a better understanding of DH's control panel-accessible .htaccess can answer your question.