I'm afraid I don't know what is causing your caller ID name issue. It would be helpful if you could try calling from some other telephone (ideally, a land line) that has a known-good CNAM entry.
As Taoman and I discussed, CNAM is flaky, period. If Callcentric can figure it out for you, great. If you set up your Callcentric account using the OBiTALK portal, then the default settings it applied would automatically enable CNAM. If you set it up locally, you may want to try deleting SP2, and then setting it up again via the OBiTALK portal, by scrolling down to the bottom of the page and selecting the other service providers link, which will then let you select Callcentric.
Aside from that, perhaps somebody else will have a brainstorm. And, yes, if this is important to you, by all means feel free to try the Simonics alternative.