G'day Badmachine,
By the way, a couple of other questions regarding B767 navigation:
Yeah, I've got time for a few more questions,
"- Are flight routes or flight plans comprised of a series of waypoints? Are such waypoints presently comprised of GPS (WAAS) data or other conventional nav-aid information? (VOR, MLS, etc)"
Flight plans are constructed using both named Lat/Long waypoints and radio nav beacons. Generally loaded from the FMC data base. Around here, Oz, there are not that many radio aids so named Lat/long waypoints are more prevalent. In the USA or Europe things would be different due to the prevalence of navaids. The waypoints can be used by GPS, MLS etc
"- Does B767 auto-pilot operation have built-in speed limitations when flying at certain minimum altitudes? (Restriction of high speeds at low altitudes that might be deemed dangerous.)"
Depending on the operating mode the autopilot protects from overspeed, underspeed and also landing gear and flap limit speeds. If there is a speed restriction which is slower than the aircraft maximum then it's up to the pilot monitor it and not exceed it.
Regards,
BH.