[GWP] IDPRCNV_SINGLEDISPLAYPRIORITY parameter for automated IDPR

I think this is described here: communities.bentley.com/.../12568.idprcnv-singledisplaypriority

Unfortunately it is only for command line iDPR but not sure how to use it for Automated iDPR. Where should i put this parameter?

I get the same error if I uses the Additional Parameters, but when pasting IDPRCNV_SINGLEDISPLAYPRIORITY=TRUE into Keyin A:
The View Last Log shows
Created : 1/5/2017 7:23:13 AM
Executing command: C:\Bentley\GeoWebPublisher\iDprCnv.exe -input="c:\bentley\geowebpublisher\engine\workspace\projects\examples\geospatial\whistler\dgn\parcelsxm.dgn" -db="ODBC,PubWhistler,parcel_id" -overwrite -reprojection="UTM83-10,EPSG:4326,C:\Bentley\GeoWebPublisher\Engine\GWPMSEngine\GeoCoordinateData" -tooltip="[roll_no]" -symbologymode=PIXEL -type=DGN -pentable="C:\Bentley\GeoWebPublisher\Examples\Data\Parcel.tbl" -keyina="IDPRCNV_SINGLEDISPLAYPRIORITY=TRUE" -resolutionFactor=1 -highPrecision=1 -output="C:\Bentley\GeoWebPublisher\iDpr/183b1175-f90c-44a5-b4a0-94a6145913e3.idpr" -trace
Trace: Parameters list
Trace: -f=C:\Windows\TEMP\tmpE278.tmp
Trace: -db=xxxxx
Trace: Validating arguments...
Trace: Arguments have been validated successfully.
etc.

Regards
Arne

But IDPRCNV_SINGLEDISPLAYPRIORITY is not a Key-in that can be executed in Microstation. It is configuration variable or windows environment variables. I could set it as environment variable but then it will affect all iDPR publishing.