The Update Master data will synchronized the Carriers and the bookingprofiles
Packages are not retrieved from the sendcloud portal. Create your packages manual in Business Central within the Sendcloud setup. Choose package type from the Ribbon and insert your default package types.

For the mapping of the Carriers see the nShift Transsmart or nShift Ship chapter :

Mapping carriers

Need more help with this?
Support Portal

Thanks for your feedback.