I've encountered an interesting situation...
I prepared a sample desktop solution, and in the course of testing it I was very annoyed to discover that the conversion worked this time. However, when I checked the resulting PDF I found it had the Evaluation Warning in the header (similar to the result you had sent me). I had added my license file to the project but I had forgotten to set it as an embedded resource. I did that and then re-ran my test. This time it hung the same way as before, so there appears to be a difference in behavior between an evaluation run and a licensed run (as well as something peculiar about this particular document).
I'm attaching the sample project for you to review.
Also, in the course of the second debug run, after about a minute waiting for the call to finish, the application went into break mode with the following message (this may have to do more with being in the debug environment, so I don't know how helpful it will be):
Managed Debugging Assistant 'ContextSwitchDeadlock' has detected a problem in 'C:\Users\klukes\Documents\Visual Studio 2015\Projects\SampleTest\SampleTest\bin\Debug\SampleTest.vshost.exe'.
Additional information: The CLR has been unable to transition from COM context 0x17c6048 to COM context 0x17c6100 for 60 seconds. The thread that owns the destination context/apartment is most likely either doing a non pumping wait or processing a very long running operation without pumping Windows messages. This situation generally has a negative performance impact and may even lead to the application becoming non responsive or memory usage accumulating continually over time. To avoid this problem, all single threaded apartment (STA) threads should use pumping wait primitives (such as CoWaitForMultipleHandles) and routinely pump messages during long running operations.
Thanks,
Kevin Lukes
Programmer/Analyst
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