I didnt' think the 3546 could be flipped to a pure bridge...huh, could you toss me the link you have for that from Netopia? The first time I ran across these devices (also on SBC business DSL) and I was setting up a WAN over DSL, I had to replace them with the lower but basic Efficient modems so I could use Sonicwall routers. SBC support told me the Netopias could not be flipped to simple bridges. I called their support several different times and got that answer from different peeps, so I believed them and didn't pursue the matter with Netopia.
More towards your issue, specifically what ports are being forwarded? And have you tested anything else such as Remote Desktop (3389) to see if a more basic service can function publically?
Double check the WAN IP address of your Netgear router, making sure it's a legit public IP address?
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