SMCD3G-CCR pseudo-bridge but RDP ports are blocked

The notorious SMCD3G-CCR strikes again! It's in pseudo-bridge mode because I have a static IP and can't use true bridge as shown below. The SMC is connected to a LinkSys LRT214 router. The problem is that the SMC is block ports. After many hours, I was able to coax it into opening RDP port 3389 by removing the router and plugging in a Windows box directly with the static IP and 3389 enabled and exercised. After returning to the LRT214, 3389 still was open and operational. But other ports are still showing blocked. Doing the same trick but with the Windows RDP port changed via regedit to 3394 and restarting, that port remained blocked. I've seen countless postings of this trouble with this SMC. Comcast looks at the config and says it's not blocking any ports, notwithstanding the fact that ping.eu says yes it is blocking, and RDP doesn't answer as a result. True bridge would probably work, but not with a static IP. Is there a different modem that might work?