Version 4.09
OK, I think I have been able to recreate this conundrum. I created the following flight plan (probably irrelevant): KHHR LAX V23 GMN V23 EHF V23 LIN ROZZY KAUN. During the flight, I brought up the flight plan, scrolled down to KAUN, clicked Opts. Then went to Info on AUN and then View Charts. Selected the GPS Approach. Then I clicked the More button.
I think the problem happens after clicking the More button. From that point on, hitting the X brings you back to the Info on AUN.
Hope this works the same way when you try it.