The file can be an fsdb file, a task-format file as txt or json, any existing Taskmap Viewer html file, or an igc file containing C Records.
The Taskmap Viewer will probably be inside an iframe on a page, so make sure that the url points to its content, and not to the page containing it.
The Taskmap Viewer automatically displays the task data in one of two styles, depending on the size of its container. If it detects other viewers on the page, it will start by showing a static map that can be activated as required.