Create custom transaction on the base of RSDMD to populate bw master data

Hello All,

my client is asking me if there is a possibility to create a custom transaction on the base of standard transaction RSDMD to populate the master data manually allowing the users to see only selected master data.

we have a SAP BW and APO on the same system.

the client ask if we can have a control level if the master data call other infoobjects for example (hierarchy market call the infoobjects LEV1, LEV2 etc) we can do in a manner that is not possibile to insert new valus but only to combine existed values?

Thanks for All

Bilal