I've checked all the File Health Check errors, and there is nothing to worry about. At some point I will go through some of the older add-ons and re-release them with the latest versions of all the files so that this doesn't happen again.
As for your other error, if this was a one off it probably happened while you were uploading a file. It happens when you have part uploaded a file and someone tries to access a page on your site that uses that file. Using our
Install and Upgrade by Waindigo add-on and uploading zip files can help avoid this.