Update 6/04 on my problem:
Got back excellent technical support info from D Q Technology on putting my EBay purchased Visionnet 200ER modem/(router) to factory defaults (from the proprietary Earthlink junk in it).
Instructions worked great, DQ had emailed the updated firmware and all went well. However, despite carefully comparing all my Qwest parameters in existing modem with the 200ER, I was unable to make it work with Qwest. Diagnostics kept reporting PPP handshake problem and I can't see where it differs from my Qwest modem PPP parameters. Oh well, I am giving up for the present on this Visionnet and going back to EBay with a list of Jeff's suggested modems (no router).
I checked the dslreports faq above on putting my Qwest Actiontec GT701 in bridging mode, but apparently that won't work if PPPoA is required, and it IS in my case.... sigh . . .
Ed