Hi
I've had similar problems, and I'm still going through some of them - but I can get into the samples, etc.
May be useful to bounce ideas back & forth, seeing as we're both doing something that seems to be largely undocumented. Let me know if you want some help / ideas and maybe we can help each other out!
In the meantime, check that you're using the right port. I see you're using 8700. SAP generally uses port 50000 upwards for the Java server (you may be using the HTTP port for the ABAP system?). Try using port 5XX00 (where XX is your central instance number) and see if that works.
Cheers
Stuart