After a few trials we got this configuration to work the best. We connected the OOMA box to an open port of the router (netgear wireless), as in fig.2B? without connecting a computer to the OOMA.
The cable provider uses some kind of black switching box located inside house. Into it is connected a power line, a cable, and a phone line. All needed to do was disconnect the phone line from box (check have no dial tones to any phones), then connect this to the wall port on OOMA box. Gave it about 10 minutes to update and all the phones in house worked with OOMA dial tone. In this setup there was no need to disconnect box outside, was quick and easy. Apparently the cable is bringing in the phone signal to this box, then converts it inside the box, and sends it out to all phone jacks. I am thinking they really are doing exactly what OOMA is doing but charging you for the phone service. I may have to go into business