The code will be something like:
*XDIM_MEMBERSET AUDITTRIAL = AUDITFORBUDGET // AUDITTRAIL ID where BUD figures are stored
*XDIM_MEMBERSET INTERNAL_ORDER = BAS(P_TOTAL)
*XDIM_MEMBERSET FORECAST_ACCOUNT = BAS(B_1000)
*XDIM_MEMBERSET COSTCENTRE = NO_CC
*XDIM_MEMBERSET CUSTOMER = NOCUS
*XDIM_MEMBERSET VENDOR = NOVEN
*XDIM_MEMBERSET VERSION = BUD
*WHEN FORECAST_ACCOUNT
*IS *
*REC(EXPRESSION=(([CUSTOMER].[ALL],[VENDOR].[ALL],[VERSION].[ACT],[AUDITTRIAL].[LN])==0) ? -%VALUE% : 0,AUDITTRAIL=REVERSAL)
*ENDWHEN
Vadim