For step 3, Create transport request or use default transport request you need access to Export Customizing Transports app. You don't have access to this app with the SAP_BR_ADMINISTRATOR role but you need the role SAP_BR_BPC_EXPERT and in particular business catalogs SAP_CORE_BC_BCT_TRN_MNG_PC and SAP_CORE_BC_BCT_TRN_REL_PC assigned to your user in order to use the app. Please mention as prerequisite.