diff --git a/crates/workshop-rs/src/settings/check.rs b/crates/workshop-rs/src/settings/check.rs
index 2c54c0b..7d91d36 100644
--- a/crates/workshop-rs/src/settings/check.rs
+++ b/crates/workshop-rs/src/settings/check.rs
@@ -3,8 +3,9 @@
 //! [`crate::Program::validate`] runs [`check_emission`] on every program, so
 //! checking raw Workshop input reports the same settings errors emission
 //! would. Members the catalog does not declare are carried as written
-//! ([`SettingsNode::Raw`], [`SettingsNode::RawValue`], or a block of them) and
-//! accepted; [`check_emission`] reports every other member the emitter would
+//! ([`SettingsNode::Raw`], [`SettingsNode::RawValue`], or a block of them —
+//! under an unknown key or a catalogued non-list key) and accepted;
+//! [`check_emission`] reports every other member the emitter would
 //! reject, without producing Workshop text. A carried member close to
 //! exactly one declared spelling is additionally reported as a
 //! [`DiagnosticSeverity::Warning`] diagnostic — a likely misspelling — by
@@ -102,7 +103,7 @@ pub(crate) fn uncatalogued_members(settings: &Settings) -> Vec<UncataloguedMembe
             full.push(PathPart::Part(node.name()));
             let catalogued = table::lookup(&full);
             let member = match (node, catalogued) {
-                (SettingsNode::Raw { .. }, _) | (SettingsNode::Group { .. }, None) => {
+                (SettingsNode::Raw { .. }, _) | (SettingsNode::Group { .. }, _) => {
                     UncataloguedMember {
                         name: node.name(),
                         span: node.span(),
@@ -333,9 +334,10 @@ fn check_member(node: &SettingsNode, path: &[PathPart<'_>], errors: &mut Vec<Set
     }
     match (node, table::lookup(&full)) {
         (SettingsNode::Raw { .. } | SettingsNode::RawValue { .. }, _) => return,
-        // Mirrors `settings_member`: an uncatalogued block is emitted as
-        // written; only its leaves must have a written form.
-        (SettingsNode::Group { children, .. }, None) => {
+        // Mirrors `settings_member`: a block is carried as written whether
+        // or not its key is catalogued; only its leaves must have a written
+        // form (#412).
+        (SettingsNode::Group { children, .. }, _) => {
             for child in children {
                 check_member(child, &[], errors);
             }
diff --git a/crates/workshop-rs/src/settings/emitter.rs b/crates/workshop-rs/src/settings/emitter.rs
index c353fde..2c6032c 100644
--- a/crates/workshop-rs/src/settings/emitter.rs
+++ b/crates/workshop-rs/src/settings/emitter.rs
@@ -231,9 +231,15 @@ impl EmitContext<'_> {
                     self.line(level, &format!("{display_name}: {value}"))
                 };
             }
-            // A block the catalog does not declare is carried as written.
-            (SettingsNode::Group { children, .. }, None) => {
-                return self.emit_opaque_group(children, name, level);
+            // A block is carried as written: under an uncatalogued key
+            // verbatim, and under a catalogued key as an undeclared value
+            // with the key's display name (#412).
+            (SettingsNode::Group { children, .. }, entry) => {
+                let block_name = match entry {
+                    Some(entry) => self.member_display_name(&full, hero, entry)?,
+                    None => name.to_string(),
+                };
+                return self.emit_opaque_group(children, &block_name, level);
             }
             _ => {}
         }
diff --git a/crates/workshop-rs/src/settings/parser.rs b/crates/workshop-rs/src/settings/parser.rs
index f7d43c7..909b536 100644
--- a/crates/workshop-rs/src/settings/parser.rs
+++ b/crates/workshop-rs/src/settings/parser.rs
@@ -230,6 +230,13 @@ impl ParseContext<'_> {
             _ => return Err(self.malformed("settings entry has no leaf key", self.previous())),
         };
         if matches!(self.peek().map(|token| token.kind), Some(TokenKind::LBrace)) {
+            // A block under a catalogued non-list key carries an undeclared
+            // value: the pinned source compilers write it as an opaque
+            // block, so it parses like an uncatalogued-key block (#412).
+            if !matches!(entry.kind, KeyKind::ListMap | KeyKind::ListHero) {
+                self.pos += 1;
+                return self.settings_opaque_group(name, start);
+            }
             self.expect(TokenKind::LBrace, "expected '{' after settings list")?;
             let mut elements = Vec::new();
             while !matches!(self.peek().map(|token| token.kind), Some(TokenKind::RBrace)) {
@@ -266,11 +273,7 @@ impl ParseContext<'_> {
                             &value,
                         )
                         .unwrap_or(value.as_str()),
-                    _ => {
-                        return Err(
-                            self.malformed("only settings lists may use braces", self.previous())
-                        );
-                    }
+                    _ => unreachable!("non-list kinds return an opaque group above"),
                 };
                 elements.push(SettingsListElement {
                     value: canonical.to_string(),
diff --git a/crates/workshop-rs/tests/settings_pipeline.rs b/crates/workshop-rs/tests/settings_pipeline.rs
index 8ea6532..13e4933 100644
--- a/crates/workshop-rs/tests/settings_pipeline.rs
+++ b/crates/workshop-rs/tests/settings_pipeline.rs
@@ -1602,6 +1602,113 @@ fn typed_uncatalogued_members_localize_catalogued_keys_only() {
     assert!(localized.contains(": Sometimes"), "{localized}");
 }
 
+#[test]
+fn issue_412_catalogued_key_block_round_trips_as_written() {
+    // A block under a catalogued non-list key carries an undeclared value:
+    // the pinned source compilers emit this shape, so parse, check, and
+    // emit treat it as an opaque block under the key's display name.
+    let source = r#"settings
+{
+    lobby
+    {
+        Map Rotation
+        {
+            a
+            b
+        }
+    }
+}
+rule("r")
+{
+    event
+    {
+        Ongoing - Global;
+    }
+    actions
+    {
+        Wait(1, Ignore Condition);
+    }
+}
+"#;
+    let program = parser::parse(source, &catalog(), &en()).expect("source parses");
+    program.validate().expect("a carried block is accepted");
+    let emitted = emitter::emit(&program, &catalog(), &en()).expect("emits");
+    let lines: Vec<&str> = emitted.lines().map(str::trim).collect();
+    for line in ["Map Rotation {", "a", "b"] {
+        assert!(lines.contains(&line), "{line:?} in {emitted}");
+    }
+    // The emitted text reparses, validates, and re-emits identically.
+    let reparsed = parser::parse(&emitted, &catalog(), &en()).expect("emitted text reparses");
+    reparsed.validate().expect("emitted text validates");
+    assert_eq!(
+        emitter::emit(&reparsed, &catalog(), &en()).expect("re-emits"),
+        emitted
+    );
+    // The carried block is a residual under its canonical key, not a
+    // misspelling.
+    let issue = program
+        .semantic_issues(&catalog())
+        .into_iter()
+        .find(|issue| issue.name == "mapRotation")
+        .expect("the carried block is a residual");
+    assert_eq!(issue.suggestion, None);
+    assert_eq!(
+        issue.classification,
+        semantic::ResidualClassification::ProjectDefinedConstruct
+    );
+    assert_check_compile_parity(source);
+}
+
+#[test]
+fn issue_412_catalogued_key_block_emits_the_display_name() {
+    // A `SettingsNode::Group` under a catalogued key writes the localized
+    // display name with opaque children; an uncatalogued key keeps its
+    // authored name.
+    use workshop_rs::settings::{Settings, SettingsNode};
+
+    let raw = |name: &str| SettingsNode::Raw {
+        name: name.into(),
+        value: String::new(),
+        span: None,
+    };
+    let mut program = workshop_rs::Program::new();
+    program.settings = Some(Settings {
+        span: None,
+        children: vec![
+            SettingsNode::Group {
+                name: "lobby".into(),
+                children: vec![
+                    SettingsNode::Group {
+                        name: "mapRotation".into(),
+                        children: vec![raw("a"), raw("b")],
+                        span: None,
+                    },
+                    SettingsNode::Group {
+                        name: "team1Slots".into(),
+                        children: vec![raw("x")],
+                        span: None,
+                    },
+                ],
+                span: None,
+            },
+            SettingsNode::Group {
+                name: "gamemodes".into(),
+                children: Vec::new(),
+                span: None,
+            },
+        ],
+    });
+    program.validate().expect("carried blocks are accepted");
+    let emitted = emitter::emit(&program, &catalog(), &en()).expect("emits");
+    let lines: Vec<&str> = emitted.lines().map(str::trim).collect();
+    for line in ["Map Rotation {", "a", "b", "Max Team 1 Players {", "x"] {
+        assert!(lines.contains(&line), "{line:?} in {emitted}");
+    }
+    let localized = emitter::emit(&program, &catalog(), &zh()).expect("emits zh-CN");
+    assert!(!localized.contains("mapRotation"), "{localized}");
+    assert!(!localized.contains("Max Team 1 Players"), "{localized}");
+}
+
 #[test]
 fn issue_360_opaque_settings_remain_verbatim() {
     // Unrecognized leaf members and `settings.workshop` payloads stay
diff --git a/docs/language-support/settings.md b/docs/language-support/settings.md
index dc01804..a1f4e6e 100644
--- a/docs/language-support/settings.md
+++ b/docs/language-support/settings.md
@@ -138,6 +138,9 @@ rejected, so a project can keep settings the catalog has not caught up with
   or a bare `name`);
 - a braced block whose key is unknown parses to a `SettingsNode::Group` of
   such leaves, emitted as the same block;
+- a braced block under a catalogued non-list key also parses to a
+  `SettingsNode::Group`: the key emits under its display name (localized)
+  while the block contents stay as written;
 - a catalogued key whose value is not a declared enum member, and an unknown
   `name:` with nothing after the colon, parse to `SettingsNode::RawValue`.