DeathSlam

I am looking to book some LATAM flights in Chile and Brazil in January 2025.
So I have time to try to get things sorted as the flights are not even on sale yet.

I have tried to join LATAM Pass so I can status match and get access to lounges and seat assignments. It doesn't seem to work online so I have called their contact centre who say 'they will email me'. Is this really the only way to create an account for someone from the UK?

When searching for flights on the website I can't seem to do any multi-flight itineraries. Only one flight at a time or returns. Is this expected?
Google flights lets me search for the multiple stops and prices one way, but this is not achievable inthe link to the LATAM site.
I would prefer a single ticket as this usually makes negotiation IIROPs easier (although I see LATAM has a policy that works for this on seperate LATAM tickets anyway if they are within 24hrs)

As a UK resident would I be best using the UK site to book flights or should I used the Chile site or the Brazil site? Some prices are very different across sites, but for the flights I am looking at the UK\SA prices are prety much the same.

I did try searching for this information but couldn't find it (although I did find some other useful information on the way).

DeathSlam

I have managed to answer one of the questions. Registration didn't work from Firefox, but worked from Chrome so there may have been some setting that was the problem.