You do not need to run setgenerate true to mine PoB. In order to mine PoB, just burn coins and the client will start automatically. If you turn off and then turn on the client, the client will automatically start PoB mining on the old coins. If your client is off, it will not be mining PoB, the client has to be on.
Does the wallet have to be unlocked for this?
Would it work on linux with slimcoind?
Thanks!