I've created a menu based off of the Adapt Box Menu but with an additional "Topic" section that I want to be able to edit in the Authoring Tool. I've been able to edit this topic section within the framework but I'm failing at getting the properties.schema to work. I've tried a few different ways but here is what I've currently got going:

{
"type": "object",
"$schema": "http://json-schema.org/draft-04/schema",
"id": "http://jsonschema.net",
"$ref": "http://localhost/plugins/content/contentobject/model.schema",
"globals": {
"ariaRegion": {
"type": "string",
"required": true,
"default": "Menu",
"inputType": "Text",
"validators": [],
"translatable": true
},
"durationLabel": {
"type": "string",
"required": true,
"default": "Duration:",
"inputType": "Text",
"validators": [],
"translatable": true
},
"topicLabel": {
"type": "string",
"required": true,
"default": "Topic",
"inputType": "Text",
"validators": [],
"translatable": true
},
"menuItem": {
"type": "string",
"required": true,
"default": "Menu item.",
"inputType": "Text",
"validators": [],
"translatable": true
},
"menuEnd": {
"type": "string",
"required": true,
"default": "You have reached the end of the menu.",
"inputType": "Text",
"validators": [],
"translatable": true
}
},
"properties": {
"pluginLocations": {
"type":"object",
"required":true,
"properties":{
"config": {
"type":"object"
},
"course": {
"type":"object"
},
"contentobject": {
"type":"object",
"properties": {
"_boxmenu": {
"legend": "Box Menu",
"type": "object",
"required":false,
"properties": {
"_topic": {
"type": "string",
"required": false,
"title": "Topic",
"inputType": "TextArea"
}
}
}
}
},
"article": {
"type":"object"
},
"block": {
"type":"object"
},
"component": {
"type":"object"
}
}
}
}
}

Any help is greatly appreciated! Thank you.