all content types

Hi, i am usiung h5p plugin for wordpress and the actual wordpress-version 5.4.1 reports in the plugin list:
compatible until 5.3.3
this plugin is untested for your version of wordpress.

Question 1: Is is unsafe to use h5p on the current wordpress 5.4.1?

Question 2: Or do I have migrate back (all the other plugins, theme-development, ...) to the last compatible 5.3.3 Version?

I have a free account for just over a year and until recently all of the existing content types were available when creating new content.

Back in about a week when I select Create New Content only 13 content types are available! I wonder if this is a new restriction on a free account or is it a matter of editing these content types and therefore they aren't available at the moment? If this is a restriction, I think it would be nice if a notice was posted on the web page or something like that ...

Thanks in advance

best regards

Hello,

First of all I want to think the community for this great project.

Second, I found this H5p client enabling installation of the app in a Node environment (instead of PHP). https://github.com/h5p/h5p-cli/
As I'm a bit noob and not really a developer, I didn't know how to use it. My specific question is regarding the h5p-content/blanks folder. I want to know what goes there exactly to be able to run the app server?