Can I use SAP Delivered SWCV and Namespaces

Hi,

Can I use SAP Delivered SWCV and Namespaces to put my own objects on Design time?

In other word,

I have SRM SERVER 5.0 in my XI Repository and under that SAP has also provided all the different Namespaces and related Design time objects for Sender side.

Can I go ahead and use the same name space to put custom developed Receiver side objects?

If yes, Can I use the regular transport by filesystem to export the whole SRM SERVER 5.0 and import in to QA/PRD environment.

As in QA and PRD the SWCV is already there from intallation (Applied SRM specific content during post installation).

Thanks in Advance.

-Adrean.