Policy Client/Server + Tune + External Simulator not working

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  • High: It blocks me to complete my task.

I am trying to use SAC with Policy Client/Server with Tune, similarly to what is reported in the example @ ray/rllib/examples/serving/cartpole_server.py at master · ray-project/ray · GitHub.
As I start the server, I get the following error:
“Cannot create SACConfig from given config_dict! Property stdout_file not supported.”

Checking around I noticed that at Register a custom environment and runing PPOTrainer on that environment not working - #5 by PhilippWillms it is said the equivalent error for PPO is due to None being returned from a registered environment. So my question is: Is Client/Server + Tune compatible with an external simulator? (a.k.a. having None as a registered environment in the config file)