Local Peers
This will open a window that lets you control all local peers related options.  This includes automatic local peer discovery and manual peer IP entry for automatic insertion to all transfers.

Connection Protocols
All peer protocols can be enabled/disabled using these settings.  It is recommended to keep all of them enabled.

PEX Peer Exchange
PEX is a protocol extension that allows peers to exchange addresses of other peers with each other, in order to maximize the visibility between peers in the swarm.  It is usually best to leave the PEX mode set to "Send/Receive".

Auto-Ignore Bad Piece Threshold
The remote peer will be blocked if the amount of received invalid pieces exceeds this threshold.  This is a safe-guard mechanism against peers who send junk data intentionally to slow down your download.

Auto-Ignore Deprioritize Bad Piece Threshold
The remote peer will only be deprioritized if you receive too many invalid pieces from them (exceeding this threshold).  This is a safe-guard mechanism against peers with high transmission error rate, likely their internet connection is poor. Receiving too many pieces from them may negatively impact your download speed.

Auto-Deprioritize Bandwidth
Here you can configure the priority group and incoming limits of deprioritized peers.

Client Filter
This will open a window that lets you full configure the client filters that are applied to all transfers.  You can filter peers based on Client ID or their unique Peer ID.  Allows for whitelist / blacklist / exemption rules.

Web Seed Request Limiter
This opens a window to configure the Web Seed Request Limiter, which limits simultaneous web seed requests to prevent the overload of servers when downloading many different items from the same source.  Some servers will throttle remote addresses that are the source of too many requests.  This feature was designed to prevent that.