It can happen that, in DELTAGEN 13.0, Stellar GI rendering does not function in Scale mode. This occurs because the Scale client installer does not copy all necessary files to the render nodes.
Workaround for DELTAGEN 13.0:
Copy the Stellar runtime folder to the Scale clients.
1. Navigate to the folder C:Program FilesDassault Systemes3DEXCITEDELTAGEN13.0stellar-runtime
2. Copy the contents of the folder and paste them into each of the Scale clients
This problem is fixed in DELTAGEN versions 13.1 and newer.