If after following this tutorial, the green insert button is not showing next to the content, this might be related to the "Plugin Type" on the "Manage Plugin" site in Brightspace. To solve this the "Plugin Type" must be changed from "Insert Stuff" to "Insert Stuff (CIM)".
Symptom:
When trying to insert a content type from H5P in Brightspace there's no green insert button, therefore is impossible to insert.
Solution:
To fix this, firstly, the old "Remote Plugin" needs to be deleted. Go to the "Manage Remote Plugins" site and find the Plugin that is causing the trouble.
After deleting the wrong Plugin the new one needs to be added. Make sure that on the "Plugin Type" the "Insert Stuff (CIM)" is selected. The one without the (CIM) won't work.
Now that all the correct options were selected is time to try it out.
Go to the contents and create a new file. Now the insert button should be visible