Bugs in content types

I have the latest version of wordpress and when I install the pluggin the following error appear and then the plugin is not working correctly:

The plugin generated 584 characters of unexpected output during activation. If you notice “headers already sent” messages, problems with syndication feeds or other issues, try deactivating or removing this plugin.

Is anything wrong?

For Question Set, found that the "Display Result" in Question Set not working.  I checked that option, but after completing all the questions, there's no result summary, and all the comments I put in the result area, such as Greetings for pass/fail, comments for pass/fail, pass video, and fail video, does not show up.  I tried check and uncheck " Display Results", no difference.

Hello,

After wordpress upgrade to 4.2.2 version. I get the message Invalid argument supplied for foreach() in /h5p/h5p-php-library/h5p.classes.php on line 1558. How to solve?