Well I rooted around and was shocked to find u set ports in Leopard via Terminal!!!  now that's just nuts.  And what's worse, there is no understandable feedback.
sudo ipfw add allow tcp from 5020 to 5020
returns
00100 allow tcp from 0.0.19.156 to 0.0.19.156
huh? 
the results are now:
coocoo:~ CooCooforCocoaPuffs$ sudo ipfw list
00100 allow tcp from 0.0.19.156 to 0.0.19.156
65535 allow ip from any to any
which makes no sense...does a double positive = a negative?

But what's worse and really to the point, setting 5020 to open via this method did not fix my problem. Ha!

RESOLUTION!!!!
Okay, I fixed it. I turned off the mult-thread check box right above the network render box. it works. but multithread checked with local render is fine.  Why?  don't care. all is well.

thx mark, and may this thread help others.