CAI-LHR,LHR-DXB,DXB-LHR,LHR-LAX,LAX-EZE,EZE-CCS,CCS-SCL,SCL-IPC, IPC-SCL,SCL-LAX,LAX-JFK,JFK-HKG,HKG-NRT,NRT-HKG,HKG-BOM,BOM-SYD,SYD-BME,BME-MEL,MEL-LHR,LHR-CAI.

Dubai is still the problem. As I suggested earlier, you will have to do the CAI-LHR xxx HKG-DXB-LHR-MAD/BCN-CAI or vice versa if you wish to do DXB off CAI on the xONEx tickets.

You are using the North America transit twice exemption if you do not stopover twice. I would suggest that you do the LHR-LAX-EZE first. If you have run out of sectors, and I think you will, then you can just substitute LHR-EZE direct (but via GRU).

You have chosen to Asia-SWP from BOM but it would be possible to do it from NRT to SYD/MEL so you could change the Japan/India order if you wanted.

I think that the best that you can do for a 20 coupon trip is:

CAI-LHR (for the night sector in First and you return during the day/evening on Iberia in Business) - EZE (direct but via from LHR) - CCS - SCL - IPC - SCL - LAX - JFK - HKG - NRT - HKG - BOM - SYD - BME - MEL - HKG - DXB - LHR - MAD/BCN - CAI.

It is also possible to end your trip in the "Middle East" so you could end up in DXB. I do not know how you propose to start/finish the trip. You can get an off ONEx single from DXB to CAI for about US$400 in economy on Gulf/Emirates. This would give you another few sectors to play with and allow the LAX from LHR to come into play again.

Hope this helps.