diff --git a/prototypes/ptth_quic_client_gui/src/main.rs b/prototypes/ptth_quic_client_gui/src/main.rs
index 6ee835b..169c796 100644
--- a/prototypes/ptth_quic_client_gui/src/main.rs
+++ b/prototypes/ptth_quic_client_gui/src/main.rs
@@ -48,6 +48,7 @@ struct GuiClient <'a> {
 	rt: &'a Runtime,
 	frame_status: Frame,
 	ports: Vec <Port>,
+	but_add_port: Button,
 }
 
 struct Port {
@@ -56,8 +57,11 @@ struct Port {
 }
 
 impl Port {
-	pub fn open_port (&mut self, rt: &Runtime, connection_p2_p3: quinn::Connection)
-	-> anyhow::Result <()> 
+	pub fn open_port (
+		&mut self, 
+		rt: &Runtime, 
+		connection_p2_p3: quinn::Connection,
+	) -> anyhow::Result <()> 
 	{
 		let params = self.gui.get_params ()?;
 		
@@ -132,6 +136,10 @@ impl GuiClient <'_> {
 		ports_col: &mut Flex,
 		fltk_tx: fltk::app::Sender <Message>
 	) {
+		if self.ports.len () >= 5 {
+			return;
+		}
+		
 		let mut gui = GuiPort::new (fltk_tx, self.ports.len ());
 		ports_col.add (&gui.row);
 		ports_col.set_size (&mut gui.row, 30);
@@ -142,6 +150,10 @@ impl GuiClient <'_> {
 		};
 		
 		self.ports.push (port);
+		
+		if self.ports.len () >= 5 {
+			self.but_add_port.deactivate ();
+		}
 	}
 }
 
@@ -188,10 +200,17 @@ fn main () -> anyhow::Result <()> {
 	
 	col.end ();
 	
+	let relay_addr = opt.relay_addr.as_ref ()
+	.map (|s| &s[..])
+	.unwrap_or ("127.0.0.1:30380")
+	.parse ()
+	.context ("relay_addr should be like 127.0.0.1:30380")?;
+	
 	let mut gui_client = GuiClient {
 		rt: &rt,
 		frame_status,
 		ports: Default::default (),
+		but_add_port,
 	};
 	
 	gui_client.add_port (&mut ports_col, fltk_tx);
@@ -208,10 +227,6 @@ fn main () -> anyhow::Result <()> {
 			None => tokio::fs::read ("ptth_quic_output/quic_server.crt").await?.into (),
 		};
 		
-		let relay_addr = opt.relay_addr
-		.unwrap_or_else (|| String::from ("127.0.0.1:30380"))
-		.parse ()
-		.context ("relay_addr should be like 127.0.0.1:30380")?;
 		let endpoint = make_client_endpoint ("0.0.0.0:0".parse ()?, &[&server_cert])?;
 		
 		trace! ("Connecting to relay server");
@@ -261,7 +276,6 @@ fn set_active <W: WidgetExt> (w: &mut W, b: bool) {
 
 impl GuiPort {
 	fn new (fltk_tx: fltk::app::Sender <Message>, port_idx: usize) -> Self {
-		
 		let mut row = Flex::default ().row ();
 		
 		let mut input_server_id = Input::default ();
@@ -308,7 +322,6 @@ impl GuiPort {
 		let server_id = self.input_server_id.value ();
 		
 		let client_tcp_port = PortInfo {
-			relay_addr: "bogus_relay",
 			server_id: &server_id,
 			server_tcp_port,
 		}.random_eph_port ();
@@ -338,7 +351,7 @@ impl GuiPort {
 
 #[derive (serde::Serialize)]
 struct PortInfo <'a> {
-	relay_addr: &'a str,
+	// relay_addr: SocketAddr,
 	server_id: &'a str,
 	server_tcp_port: u16
 }
@@ -375,14 +388,13 @@ mod test {
 		assert_eq! (port, 49408);
 		
 		for (input, expected) in vec! [
-			(("bogus_relay", "bogus_server",   22), 62350),
-			(("real_relay",  "bogus_server",   22), 61081),
-			(("bogus_relay", "real_server",    22), 50513),
-			(("bogus_relay", "bogus_server", 5900), 60730),
+			(("127.0.0.1:4000",  "bogus_server",   22), 51168),
+			(("127.0.0.1:30380", "bogus_server",   22), 51168),
+			(("127.0.0.1:4000",  "real_server",    22), 53873),
+			(("127.0.0.1:4000",  "bogus_server", 5900), 53844),
 		] {
-			let (relay_addr, server_id, server_tcp_port) = input;
+			let (_relay_addr, server_id, server_tcp_port) = input;
 			let input = PortInfo {
-				relay_addr,
 				server_id,
 				server_tcp_port,
 			};