Tim,
Here is how you manually configure an Image in a popup for LL Widget (you need to manually edit the config_Local Layer Widget.json):
{
"type": "Feature",
"url": "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Louisville/LOJIC_PublicSafety_Louisville/...",
"name": "Traffic Cameras",
"opacity": 1,
"visible": true,
"showLabels": false,
"trackEditByLDAP": false,
"limitEditByLDAP": false,
"popup": {
"title": "{DESCRIPTION}",
"fieldInfos": [
{
"fieldName": "URL",
"label": "URL",
"visible": true
},
{
"fieldName": "ONLINE",
"label": "ONLINE",
"visible": true
},
{
"fieldName": "DESCRIPTION",
"label": "DESCRIPTION",
"visible": true
},
{
"fieldName": "LAST_UPDATED",
"label": "LAST_UPDATED",
"visible": true
}
],
"mediaInfos": [{
"title": "",
"caption": "",
"type": "image",
"value": {
"sourceURL": "{URL}",
"linkURL": "{URL}"
}
}]
},