Is there anyway to view ALL content from a pack in build mode?

Have you tried using the filter buttons on the top right above the build mode preview? I search for all items from a specific pack using the filter all the time. Does it not show ALL the content? I thought it did. I'll have to try it again and see. Perhaps try using the filter for a specific pack along with the 'Show All' option highlighted on the drop down on the left, that might work. :)