How to customize "Create a course" page

I need support in following things - Please guide ASAP. I am trying to create a website where in instructors can upload there courses? Here, my customers will be both - Instructors and Student.  I am struck on "Create a course" page where i am using "Course Custom nav" plugin. Though i am able to hide things in there which i want to show to instructors of my page like  Settings, Components,Events, Pricing as i want only Admin to handle those for all courses but i am struck with following : </div> 1.I want following settings in Set curriculum page - Current behaviour - Add Section, Add unit, Add quiz appears simultaneously when we land on Set curriculum page Expectation : Firstly Add section only appears, when added a section it should only allow to add unit and add quiz or any other section *IMPORTANT  Current behaviour - Uploaded videos are showing as attachment in add unit page and is downloadable Expectation : I need a inline playing video which should not be downloadable.  2. I dont want Instructors to see "Admin panel". I have removed top bar to enter admin panel, but getting option "Edit in Admin panel" in "Set Curriculum" section in "Add units". Please help me to know how can we remove or customise this "Set Curriculum" page to remove the button and make the look and feel of page better for instructors.

1. I want to remove "Add video" from "Create course" tab  , and not able to do so in Course custom nav pluggin which does not alter this tab. It only allows to hide/show starting settings tab. And Instructor should not be allowed to add new category also.  

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