Applying for Tier 1 Dependant Visa from Paraguay

Hi Everyone,

I have a Tier 1 Post study work visa, and my wife who is from Paraguay would like to apply for a dependant Tier 1 PSW visa to be able to work in the UK.

She is currently in the UK visiting me, and i would like to know how can she apply for the visa since there is no British Embassy or Application Centre in Paraguay. IT says on UKBA website that the application would be processed in Argentina.

Since she needs to register her biometric information as part of the process, does she need to send her application first and then book an appointment to register her biometric information or its done together?

Im asking this because instead of going to Paraguay to send the application and documents and then going to Argentina, can she just go to Argentina after booking the appointment and do everything together?

I look forward to any help.