Error Exporting: Specified cast is not valid

[LawrenceSelly]

Unity 2018.3.0f2
Error exporting: Specified cast is not valid.

UnityEngine.Debug:Log(Object)
JanusVR.JanusVRExporterWindow:OnGUI() (at Assets/JanusExporter/Codebase/Editor/Windows/JanusVRExporterWindow.cs:531)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

Tried every option checked vs unchecked on the Janus VR exporter.

Most recent build used (2.14)

Cannot even export HTML only.

[m00nwtchr]

Same problem: Unity 2019.1.1f, same version of the exporter