This is a followup for anyone searching this later (or even me).

There are 3 IATA regions. In general, IATA1 is North and South America; IATA2 is Europe, Middle East, and Africa; and IATA3 is Asia and Pacific. I could not find any place that defined each country and their IATA area - for those countries that aren't obvious.

As Al B said, you can travel in any direction within an IATA area. But, once you cross into a new area, you can not go back. I don't know if a transfer through a different area would count as going into a new area or whether it would have to be a stopover.

As for the "lite" fare, the RTW rules doc referred to in Al B's comments lists info about a "special" fare which is the same thing. It is available only for coach class. That said, both Lufthansa and Singapore said there was no such thing as a "lite" fare. I even asked about a fare for less than 26k miles and still nothing. Perhaps if I had asked for the "special coach 26k mile" fare that would have gotten a positive response. Hmmm.

Cheers, Mike