I have it working. I want to post this for others.
When you are problem-solving with the direct connection, make sure to power the router on FIRST. Then power on the OBi 2 minutes later.
When you are changing router settings, they have to be applied on the router side. THEN, you have to reboot the Obi. I disabled SIP ALG but didn't reboot the OBi. Now that I rebooted the OBi, I got the Callcentric call to go through. I am now getting 911 to work.
911 works fine, the dispatcher confirmed all data EXCEPT phone number, but the number displayed DID in fact ring my house (he asked to test it). In my area, they recommend testing 911 and they suggest Sunday mornings
.
I have opened a trouble ticket with Callcentric to see if the number displayed can be changed (it's not my Callcentric number).
Otherwise, we are ready to switch the alarm line tomorrow and then begin the porting of our landline.
I'd like to thank RonR and Stewart for their suggestions, and hope that my issues help others figure out their problems more easily.
Happy New Year to all.
Update:
Callcentric's response is that they use a hidden number to give to the 911 operator, which allows them to reach the house EVEN IF we have our phone number forwarded somewhere else. I hadn't found that on their site, it's nice to know.