H5P validation errors

I'm having trouble trying to modify the course presentation module. The course designers on my team want to use image hotspot inside of course presentation. This is what I've done so far: pulled the code from github, updated the semantics.json, built the node project, and packed the h5p file.

But when the h5p is uploaded to my moodle site it returns the following validation errors:

• A valid content folder is missing
• A valid main h5p.json file is missing

I created an h5p.json file with all the mandatory properties, and the documentation says the content folder is optional. What is going wrong here?

Here's the h5p.json file:

{
  "title": "Course Presentation",
  "mainLibrary": "H5P.CoursePresentation",
  "language": "en",
  "embedTypes": ["iframe"],
  "preloadedDependencies": [
    {
      "machineName": "FontAwesome",
      "majorVersion": 4,
      "minorVersion": 5
    },
    {
      "machineName": "H5P.JoubelUI",
      "majorVersion": 1,
      "minorVersion": 3
    },
    {
      "machineName": "H5P.FontIcons",
      "majorVersion": 1,
      "minorVersion": 0
    }
  ]
}

Here's part of the semantics.json. All that's added is image hotspot to the list of options.

[
  {
    "name": "presentation",
    "type": "group",
    "importance": "high",
    "widget": "coursepresentation",
    "fields": [
      {
        "name": "slides",
        "importance": "high",
        "type": "list",
        "field": {
          "name": "slide",
          "importance": "high",
          "type": "group",
          "fields": [
            {
              "name": "elements",
              "importance": "high",
              "type": "list",
              "field": {
                "name": "element",
                "importance": "high",
                "type": "group",
                "fields": [
                  ...
                  {
                    "name": "action",
                    "type": "library",
                    "importance": "high",
                    "options": [
                      "H5P.AdvancedText 1.1",
                      "H5P.Link 1.3",
                      "H5P.Image 1.1",
                      "H5P.Shape 1.0",
                      "H5P.Video 1.5",
                      "H5P.Audio 1.4",
                      "H5P.Blanks 1.12",
                      "H5P.SingleChoiceSet 1.11",
                      "H5P.MultiChoice 1.14",
                      "H5P.TrueFalse 1.6",
                      "H5P.DragQuestion 1.13",
                      "H5P.Summary 1.10",
                      "H5P.DragText 1.8",
                      "H5P.MarkTheWords 1.9",
                      "H5P.Dialogcards 1.8",
                      "H5P.ContinuousText 1.2",
                      "H5P.ExportableTextArea 1.3",
                      "H5P.Table 1.1",
                      "H5P.InteractiveVideo 1.22",
                      "H5P.ImageHotspots 1.9", // <-- only added this
                      "H5P.TwitterUserFeed 1.0"
                    ],
...