I don’t use the Korg for Mixer Faders (got an X-Touch for that) and just use it to send cc data to control various pieces of equipment. So I never needed to config it in the Generic Controller.
On the recordings the vocals and most guitars (but not all) are recorded. But most of the rest are VSTi’s. Occasional bits of percussion are recorded too - but the reality is the tambourine in BFD3 sounds better than the one I have across the room.