Hi,
Customizing of the transaction type, item category and the assignments are not downloaded from ECC to CRM.
This system reponse is intended. A download fo these customizing system from ECC system makes little scence because the customizing of transaction type and item category in CRMM provides many setting options which do not exist in ECC. Even they are downloaded from ECC, you must still carry out a manual maintenance. So it is decided not to provide the download, these settings have to be maintained manually in CRM system.
Please check SAP Note 425602 for the same.
Best regards,
Maggie