As of the opCharts 3.2.6 update you can now upload custom Map Icons and Backgrounds using the web interface.
Join Paul McClendon, an Opmantek Support Engineer, as he demonstrates how to insert a background image to an opCharts map.
To do this, navigate to menu -> System -> Files as shown below.
From here you can select the Resource type icon, or maps_background. Give the resource a name, then click "Browse" to navigate to the location of the desired file for the icon or background. Once the file is selected click Upload.
After the files are uploaded you can view them in the uploaded files menu at the bottom of the Files screen.
To use the newly uploaded files in a map, edit an existing map or create a new map. Select the Background Image drop-down menu and find the file you uploaded to import the desired Background image.
To use the newly uploaded Icon, select Add Node to add the desired node to the map. The menu below will open up, select the Icon drop-down menu and find the uploaded Icon image from the list and click Add.