I am very pleased to have found all of the resources on flyertalk. It is fantastic!

I am planning a LONE4 ex CAI but, am discouraged by the ability to only stop over once in North America. My plan was to start in CAI, travel around and stop in the US.... make a trip to South American (hence the LONE4) and stop back in the US on the way to Europe to finish the trip. Apparently that is not allowed. Is there any way around that restriction?

MY planned itinerary is:

CAI-LHR-BOM

overland to SIN (can't get to SIN from BOM or MAA that I can find on One World)
SIN-HKG-PEK
PEK-HKG-YVR
YVR-DFW-CLT (stop here for a while)
CLT-DFW-SCL-PUQ
PUQ-SCL-IAD (stop here- This is the problem)
IAD-LHR-MXP
MXP-LHR-CAI

If I can't add the Patagonia trip, I guess I am stuck with a LONE3 without South America and that isn't what I had in mind.

Any suggestions to re-route any of the North American Segments (or buy an add on ticket) that will make this work?

Thanks;
Edward

No. You can stop on the way over to South America OR on the way back, but not both. One of them must be a transit without stopover.

You could try the following..
cai-lhr-bom
bom-bkk-sin (though this would put you over the segment limit.. maybe just bom-bkk)
sin-hkg-pek
pek-hkg-yvr-dfw-ccs
* Buy a separate ccs-clt R/T (though not looking cheap at the moment, LIM or UIO might even be cheaper)
ccs-scl-puq-scl-mia-iad
iad-lhr-mxp
mxp-lhr-cai

* Or this could be done in reverse..
pek-hkg-yvr-dfw-clt
clt-mia-lim-scl-puq-scl-ccs
*CCS-IAD return, then you could fly direct CCS-MAD-MXP

From the oneworld validator:
1: CAI-LHR: 1st of 4 (Europe)
2: LHR-BOM: intercontinental
3: BOM-BKK: 1st of 4 (Asia)
4: SIN-HKG: 2nd of 4 (Asia)
5: HKG-PEK: 3rd of 4 (Asia)
6: PEK-HKG: 4th of 4 (Asia)
7: HKG-YVR: intercontinental
8: YVR-DFW: 1st of 6 (North America)
9: DFW-CCS: intercontinental
10: CCS-SCL: 1st of 4 (South America)
11: SCL-PUQ: 2nd of 4 (South America)
12: PUQ-SCL: 3rd of 4 (South America)
13: SCL-JFK: intercontinental
14: JFK-DCA: 2nd of 6 (North America)
15: IAD-LHR: intercontinental
16: LHR-MXP: 2nd of 4 (Europe)
17: MXP-LHR: 3rd of 4 (Europe)
18: LHR-CAI: 4th of 4 (Europe)

Congratulations!! Valid itinerary!!! - (41347 miles)

Though pricewise it may end up being a wash.. buying a LONE3 + South America ticket ($2000 + $1000) might be the same as a LONE4 + add-on ($2400+$600).