How are you developing your plug-in? C#, C++ or something else? With Visual Studio 2017?
If you build a debug version of your plug-in you should start Rhino through the debug configuration. If you used RhinoCommon (C# etc) you should change the exception settings after starting to breal on any CLR exception, then cause the crash. Same really for C++, except change to break on any C/C++ exception.
My best guess is that you did something wrong.
Above will pinpoint where exactly things go wrong, which in turn will tell you hopefully why.
You might find a file with the name
RhinoCrashDump.dmp on your desktop. Zip it up and upload it with a reply, maybe some kind soul can have a look - or open the file in VS and see for yourself.
Btw, you also may want to ensure you are on the latest SR (6.6). Bugs get fixed all the time in Rhino.