Amine,
Are you referring to uploading reports to the BPC environment via BW? If so, then you can use UJFS in SAP GUI to upload. Just be mindful that data files should be uploaded via Upload for DM (Data Manager) and others should be loaded via Upload from PC. Otherwise, you will have issues when you go to validate your transformation file.
I am not sure if this is what you are looking for or not. If not, could you provide some add'l info to clarify?
Jeff