I have two map document templates for ANSI D (one portrait and one landscape) added in ArcGIS Desktop's directory at C:\Program Files (x86)\ArcGIS\Desktop10.4\Templates\ExportWebMapTemplates. I follow the guide here and publish the GP service, Asynchronous.
I add the service to a Print widget in WAB Dev, and the two templates show up as options in the Layout selection box. The process fails for these two options, but succeeds for any of the other existing options (MAP_ONLY, Letter, Tabloid, etc.). The server logs in Manager and the messages in the jobs directory are not helpful.
Has anyone created a custom print service using ANSI D?