Topic: Image resize with Fix Layout

I am using fixedLayout:Boolean = true so I could place precisely my Back button, caption, title, thumbnail and Next/Previous  arrows.

My problem is by doing so, my Image Area is also fix and no scroll are showing up, preventing the display of the main image.  I don't mind having the Image Area resizing but could not figure it out.

Thanks for your help
Test site: www idarivard com/viewer/index html