I'm a developer working on a Windows forms application for a client. My client's users are using AutoCAD 2016 to create DWG files. They have an existing Windows application that creates batch plot lists as ".bp3" files, but they don't have the source code for the app. The new app I'm writing will replace their existing app, and needs to create batch plot list files outside of AutoCAD. I have the dlls from the ObjectARX SDK included in my Windows project and I've got some C# code that compiles, but fails at runtime (System.InvalidProgramException). I'm trying to use DsdEntryCollection and DsdEntry objects. The app I'm working on will be installed on PCs that also have AutoCAD installed. Am I approaching this from the wrong angle? Is there an easier way to create batch plot list files that can be opened and plotted from in AutoCAD? My experience with AutoCAD is about 20 years old - so any input here would be greatly appreciated. Using Visual Studio 2015.