Bugs in content types

I have created many interactive videos in the past, but all of a sudden, I no longer get a "SAVE" button on the page when I try to create new content. As I result, I can't SAVE my work. The "Create" button is the only thing on the screen. My plugin is up to date, but only my old project files are working propertly. What can I do?

When you user multiple choice you can "check the answer" even if no answer is selcted by the user. That makes no sense.

If you choose to check without an answer given nothing happens and only the button "show solution" (if activated) appears. If you then click it it says "Answer required"  (or similar) but you have no chance of giving an answer anymore and you are stuck with the error. There is something wrong with this process.

- You should definitely not be able to "check" an answer that has not been given.

I tried to incorporate different features with the "Column layout" in Moodle. For example the Drag and Drop feauture and the Multiple Choice feature. There I wanted to upload an image. This is really important, especially for the Drag and Drop feature. I have no problems uploading it, but other participants of the Moodle course can not see it. Why is this so and what can I do against it?

Thank you for your help!