I am testing my plugin using the latest WIP. Compiled the plugin using VC 2017 and RhinoCommon 6.
The plugin loads by dragging and dropping into Rhino 6 and works as expected.
By invoking Options->Plugins, Rhino Crashes.
Initially I thought that it might be some specific code in my plugin which causes the crash.
I created an empty plugin (Import Plugin type) using the Visual Studio wizard, with all default values. Rhino behaves the same way as described above.