To import an H5P unit to a course, visit the course's dashboard, either as an administrator or an instructor and from the course dashboard, click on the Add content button (1), next click the Add unit (2) option.
This will get you to the Add new unit page where you can add new content to your course. Provide a name for your Unit and then select the source of the unit to be a file (3). This gives you the option to either select (4) your course's file or to upload a new file.
Select upload a file and upload your .h5p file (which is your unit). eFront will take care or the rest, by importing your H5P unit to the course. Click to save the unit and you are done. You have just imported your H5P unit.
To export an H5P unit of a course, visit the course's dashboard, either as an administrator or an instructor. Here you will see a list of all your course's units. Find the H5P unit you want to export and click to view that unit.
Have in mind that you should not click to edit that unit, rather just view it. Once you click to view this unit you shall be presented with the unit's contents. Also, notice that, on the top corner of your unit, there is an Edit button.
Click on the caret next to that button (1) and, among the options that will appear, you'll find the Export option (2). Click on this option to export the H5P unit, which will prompt you to download the .h5p file of that unit.