After Update Plugin and Theme no longer function

Hello,
after I downloaded the latest version of WordPress (4.5.2.), I can not edit my theme and the plugin “Gallery by Supsystic” does not work properly.

Here is the explanation:
– Theme (Spacious Pro):
Once I want to customize the theme, it only loads a blank page and the top left of the area (ticks, “Publish & Save Button” and “your adjustment”)

– Plugin “Gallery by Supsystic:
I can not create a new gallery here. I can choose either a template nor click Save. And also add any new photos more.

Can anybody help me

Greeting laura89