You can follow the instructions on the TN 15986, but a few things can be wrong.
If your portal is installed over Windows do not use the backslash character () on the zip path
If you use the path like the command bellow, you get the “zip file not found exception” and a Build Failed message.
./ConfigEngine.sh webdav-deploy-zip-file -DTargetURI=dav:themelist/newtheme/ -DZipFilePath=d:tmpnewtheme.zip -DUpdateMode=merge
You need to use the slash character on the file path
./ConfigEngine.sh webdav-deploy-zip-file -DTargetURI=dav:themelist/theme/ -DZipFilePath=d:/tmp/newtheme.zip -DUpdateMode=merge
You need to put the wasadmin and portaladmin passwords on wkplc.properties.