their Simple Pay guides point to FPS functions for "advanced" usage. do you auth first and capture on shipment without relying on FPS functions (or widget check

their Simple Pay guides point to FPS functions for "advanced" usage. do you auth first and capture on shipment without relying on FPS functions (or widget checkout)? https://amazonpayments.s3.amazonaws.com/FPS_ASP_Guides/ASP_Getting_Started_Guide.pdf https://amazonpayments.s3.amazonaws.com/FPS_ASP_Guides/ASP_G... https://amazonpayments.s3.amazonaws.com/FPS_ASP_Guides/ASP_Advanced_Users_Guide.pdf https://amazonpayments.s3.amazonaws.com/FPS_ASP_Guides/ASP_A...