Whatever is causing the problem appears to have been introduced in v1.41. I moved the code back to version 1.4 and everything works as expected.
-Larry
When you get the exception in your program, and the .NET unhandled exception dialog pops up, press "Continue" on your debug and you should get the red "Application Error" window that will have a complete list of the exceptions and inner exceptions and the stack traces of all of the exceptions concatenated together. That should give me a clue where it's coming from. You can copy/paste the content of that window and post it here.