Ever set up a SOHO ISDN router? Whoo boy. Fasten your seat belts. I have done it with several products and I must say the vendors have sure gone out of there way to make it impossible.
Here's a great diagnostic:
(516,1520650) c021: Automaton Layer Started
For the un-hip, "c021" is PPP LCP, or link control protocol. It's documented in an RFC, which I'm sure most people have on-line. Not. How about "Call connected. Starting PPP". Gosh, wouldn't that be a nice message.
The box in question does not even tell you when the PPP negotiation fails. No, that would be far to easy. I think you should have to dive into the trace buffers to bring any product up.