Changing BPC Data Directly in BW

Hi Experts,
We would like to perform a calculation using BW rather than BPC.
The adjustment would occur recording a separate AuditID (datasource ID) to record a trail of the changes.

Issue is that we are using BW tools e.g. transformations or other to change a BPC consolidation cube.

We already went through the process (unsuccessfully) of trying to perform the adjustment in BPC via ABC or Script Logic.

Changes to config would have to be done via a BW resource rather than a Finance administrator.

Any thoughts re changing data in this manner?

Thanks

Eyal Feiler