URGENT! Refering to #453416 (Elliott) 2.6. "Several elements disappear …"

I wrote:

“Several elements disappear … maybe coinciding with an automatical WP upgrade
Pages were automatically converted into posts and the menu disappeared except for “home”. I could “repair” it with the Plugin “Post Type Switcher”. But there are still many problems on the website. When changing individual elements, it happens that other elements disappear…, for example when updating a text it happens that afterwards the headline of another text block will disappear on the same side or with changing a picture a text disappears! … Sometimes the navigation disappears from single pages … what’s going on? It ist urgent because we have to go online soon. Could you please help me with support?”
and:
Page “Philosophie”:
The Logo moves across the top of the page and the navigation disappears.

You wrote:
“Hey!

@Nic_007, You have the header set to transparent so the content is going to display beneath it. In your Philosophie page you’ll want to set the header style option to “No transparency”.”

But:
The header ist set “transparent & glassy header” like on all the other pages that work. I don’t understand your answer. I still have no solution for my other questions (from 2nd of june):
“When changing individual elements, it happens that other elements disappear…, for example when updating a text it happens that afterwards the headline of another text block will disappear on the same side or with changing a picture a text disappears!”

Could you please help me? Thx in advance!