Here's a collection of various useful files, mostly pretty up to date - http://www.hardlink.com/~markdu/OWFiles/

I don't think the Circle fare works for you as it limits stopovers in the same city; in your case Tokyo would be the knockout.

Also, IIRC Global Explorer fares ex-USA are higher than comparable-class *ONE3 RTW tickets, so although you'd be able to use JAL, you might end up paying more than you need to, esp. given you can limit your Asian segments to 4 by flying ORD-NRT-HKG-SIN-HKG-NRT-Europe.

You mentioned mileage accumulation in passing, and of course that's a key benefit of the OWE over the GlobEx, especially if you want to contribute some of your own $ by adding additional segments somewhere. (With the continent segment limits, you can't use all 20 coupons on an xONE3 without purchasing some additional ones - 3 intercontinentals, 6 NA, 4 Eur, 4 Asia = 17.) Even so, you could easily accumulate 45K+ BIS miles on a 3-continent RTW, enough to move you quite some ways along the EXP path (if you fly in business class or higher, based on qualifying points.)