diff --git a/crates/altium-codec/src/altium_decode.rs b/crates/altium-codec/src/altium_decode.rs
index 5cb462b..e343d3d 100644
--- a/crates/altium-codec/src/altium_decode.rs
+++ b/crates/altium-codec/src/altium_decode.rs
@@ -354,6 +354,7 @@ fn decode_sym_graphic(txt: &str, rec: &str) -> Option<Graphic> {
             y2: coord("Corner.Y"),
             width,
             filled: txt.contains("|IsSolid=T"),
+            fill_style: None,
         }),
         "11" => Some(Graphic::Circle {
             cx: coord("Location.X"),
diff --git a/crates/altium-codec/src/kicad.rs b/crates/altium-codec/src/kicad.rs
index 97ec9e4..5130db3 100644
--- a/crates/altium-codec/src/kicad.rs
+++ b/crates/altium-codec/src/kicad.rs
@@ -186,7 +186,14 @@ fn import_symbol(text: &str, wanted: &str) -> Result<Symbol> {
         texts: import_symbol_texts(drawing),
         designator_prefix: Some(prefix),
         footprint: None,
-        parameters: Vec::new(),
+        parameters: props.iter().filter_map(|p| {
+            let name = p.atom_at(1)?;
+            if matches!(name, "Reference" | "Footprint") { return None; }
+            let effects = p.child("effects");
+            let hidden = effects.map(|e| e.child("hide").and_then(|h| h.atom_at(1)) == Some("yes")
+                || e.items().iter().any(|i| matches!(i, Sx::Atom(a) if a == "hide"))).unwrap_or(false);
+            Some(crate::model::Parameter { name: name.into(), value: p.atom_at(2)?.into(), visible: !hidden })
+        }).collect(),
         pin_numbers_hidden: Some(has_hide("pin_numbers")),
         pin_names_hidden: Some(has_hide("pin_names")),
     })
@@ -259,6 +266,7 @@ fn import_symbol_graphics(root: &Sx) -> Vec<crate::model::Graphic> {
             out.push(Graphic::Rect {
                 x1: to_mil(s[0]), y1: to_mil(s[1]), x2: to_mil(e[0]), y2: to_mil(e[1]),
                 width: width_of(g), filled: filled_of(g),
+                fill_style: g.child("fill").and_then(|f| f.child("type")).and_then(|t| t.atom_at(1)).map(str::to_owned),
             });
         }
     }
diff --git a/crates/altium-codec/src/kicad_export.rs b/crates/altium-codec/src/kicad_export.rs
index 7fb021d..76d3a44 100644
--- a/crates/altium-codec/src/kicad_export.rs
+++ b/crates/altium-codec/src/kicad_export.rs
@@ -151,7 +151,7 @@ pub fn export_kicad_symbol_for(sym: &Symbol, ver: KicadVersion) -> String {
         s.push_str("\t\t(exclude_from_sim no)\n");
     }
     s.push_str("\t\t(in_bom yes)\n\t\t(on_board yes)\n");
-    // properties (Reference above the symbol, Value below; metadata hidden at origin)
+    // Keep hidden metadata outside the body: native library editors can display hidden fields.
     let prop = |k: &str, v: &str, x: f64, y: f64, hidden: bool| {
         let h = if hidden { hide } else { "" };
         format!(
@@ -161,13 +161,16 @@ pub fn export_kicad_symbol_for(sym: &Symbol, ver: KicadVersion) -> String {
     };
     s.push_str(&prop("Reference", &reference, cx, top + 1.27, false));
     s.push_str(&prop("Value", &value, cx, bottom - 1.27, false));
-    s.push_str(&prop("Footprint", &footprint, 0.0, 0.0, true));
+    s.push_str(&prop("Footprint", &footprint, cx, bottom - 3.81, true));
     // "" not "~": since format 20250318 a tilde is a literal tilde.
-    s.push_str(&prop("Datasheet", "", 0.0, 0.0, true));
-    // any extra parameters become hidden properties (at origin)
+    let datasheet = sym.parameters.iter().find(|p| p.name.eq_ignore_ascii_case("Datasheet"));
+    s.push_str(&prop("Datasheet", datasheet.map(|p| p.value.as_str()).unwrap_or(""), cx, bottom - 6.35, true));
+    // Preserve visibility and space metadata rows for the native editor's hidden-field view.
+    let mut metadata_y = bottom - 8.89;
     for p in &sym.parameters {
-        if !p.name.eq_ignore_ascii_case("Value") {
-            s.push_str(&prop(&p.name, &p.value, 0.0, 0.0, !p.visible));
+        if !["Value", "Reference", "Footprint", "Datasheet"].iter().any(|key| p.name.eq_ignore_ascii_case(key)) {
+            s.push_str(&prop(&p.name, &p.value, cx, metadata_y, !p.visible));
+            metadata_y -= 2.54;
         }
     }
 
@@ -212,27 +215,31 @@ pub fn export_kicad_symbol_for(sym: &Symbol, ver: KicadVersion) -> String {
 
 /// One symbol body graphic → KiCad s-expr (mils→mm via `m`).
 fn sym_graphic(g: &Graphic, m: &dyn Fn(f64) -> String) -> String {
-    let stroke_fill = |w: f64, filled: bool| {
-        let fill = if filled { "outline" } else { "none" };
+    let stroke_fill = |w: f64, fill: &str| {
         format!(
             "\t\t\t\t(stroke (width {}) (type default))\n\t\t\t\t(fill (type {fill}))\n",
             n((w * MM_PER_MIL).max(0.0))
         )
     };
     match g {
-        Graphic::Rect { x1, y1, x2, y2, width, filled } => format!(
+        Graphic::Rect { x1, y1, x2, y2, width, filled, fill_style } => format!(
             "\t\t\t(rectangle\n\t\t\t\t(start {} {})\n\t\t\t\t(end {} {})\n{}\t\t\t)\n",
-            m(*x1), m(*y1), m(*x2), m(*y2), stroke_fill(*width, *filled)
+            m(*x1), m(*y1), m(*x2), m(*y2), stroke_fill(*width, match fill_style.as_deref() {
+                Some("background") => "background",
+                Some("outline") => "outline",
+                Some("none") => "none",
+                _ => if *filled { "outline" } else { "none" },
+            })
         ),
         Graphic::Circle { cx, cy, r, width } => format!(
             "\t\t\t(circle\n\t\t\t\t(center {} {})\n\t\t\t\t(radius {})\n{}\t\t\t)\n",
-            m(*cx), m(*cy), m(*r), stroke_fill(*width, false)
+            m(*cx), m(*cy), m(*r), stroke_fill(*width, "none")
         ),
         Graphic::Arc { cx, cy, r, start, end, width } => {
             let (s, mid, e) = arc_points(*cx, *cy, *r, *start, *end);
             format!(
                 "\t\t\t(arc\n\t\t\t\t(start {} {})\n\t\t\t\t(mid {} {})\n\t\t\t\t(end {} {})\n{}\t\t\t)\n",
-                m(s.0), m(s.1), m(mid.0), m(mid.1), m(e.0), m(e.1), stroke_fill(*width, false)
+                m(s.0), m(s.1), m(mid.0), m(mid.1), m(e.0), m(e.1), stroke_fill(*width, "none")
             )
         }
         Graphic::Polyline { points, width } => {
@@ -242,7 +249,7 @@ fn sym_graphic(g: &Graphic, m: &dyn Fn(f64) -> String) -> String {
             }
             format!(
                 "\t\t\t(polyline\n\t\t\t\t(pts\n{pts}\t\t\t\t)\n{}\t\t\t)\n",
-                stroke_fill(*width, false)
+                stroke_fill(*width, "none")
             )
         }
     }
diff --git a/crates/altium-codec/src/lib.rs b/crates/altium-codec/src/lib.rs
index fda14c7..65572b7 100644
--- a/crates/altium-codec/src/lib.rs
+++ b/crates/altium-codec/src/lib.rs
@@ -48,6 +48,46 @@ mod tests {
         }
     }
 
+    #[test]
+    fn background_and_outline_fill_remain_distinct_through_canonical_json() {
+        for style in ["background", "outline", "none"] {
+            let source = format!(r#"(kicad_symbol_lib (version 20231120) (generator "test")
+              (symbol "FILL" (symbol "FILL_0_1"
+                (rectangle (start -2.54 2.54) (end 2.54 -2.54)
+                  (stroke (width 0.254) (type default)) (fill (type {style}))))))"#);
+            let sym = import_kicad(&source, r#"(footprint "FILL" (layer "F.Cu"))"#, "FILL").unwrap().symbol;
+            let json = serde_json::to_string(&sym).unwrap();
+            let canonical: Symbol = serde_json::from_str(&json).unwrap();
+            let out = export_kicad_symbol(&canonical);
+            assert!(out.contains(&format!("(fill (type {style}))")), "{out}");
+        }
+        // Older libraries have only the boolean; retain their established rendering.
+        let legacy: Graphic = serde_json::from_str(r#"{"kind":"rect","x1":0,"y1":0,"x2":100,"y2":100,"filled":true}"#).unwrap();
+        let mut sym = two_pin_symbol();
+        sym.graphics.push(legacy);
+        assert!(export_kicad_symbol(&sym).contains("(fill (type outline))"));
+    }
+
+    #[test]
+    fn datasheet_and_metadata_survive_kicad_without_duplicate_properties() {
+        let source = r#"(kicad_symbol_lib (version 20231120) (generator "test")
+          (symbol "META" (property "Reference" "U" (at 0 0 0))
+            (property "Datasheet" "https://manufacturer.example/datasheet.pdf" (at 0 0 0) (effects (font (size 1 1)) hide))
+            (property "Manufacturer" "Maker" (at 0 0 0) (effects (font (size 1 1)) (hide yes)))
+            (property "VisibleNote" "Read me" (at 0 0 0) (effects (font (size 1 1))))))"#;
+        let sym = import_kicad(source, r#"(footprint "META" (layer "F.Cu"))"#, "META").unwrap().symbol;
+        assert_eq!(sym.parameters.len(), 3);
+        assert!(!sym.parameters[0].visible);
+        assert!(!sym.parameters[1].visible);
+        assert!(sym.parameters[2].visible);
+        let out = export_kicad_symbol(&sym);
+        assert_eq!(out.matches("(property \"Datasheet\"").count(), 1);
+        assert!(out.contains("https://manufacturer.example/datasheet.pdf"));
+        let back = import_kicad(&out, r#"(footprint "META" (layer "F.Cu"))"#, "META").unwrap().symbol;
+        assert_eq!(back.parameters.iter().find(|p| p.name == "Manufacturer").unwrap().value, "Maker");
+        assert!(back.parameters.iter().find(|p| p.name == "VisibleNote").unwrap().visible);
+    }
+
     #[test]
     fn grouped_labels_survive_kicad_and_refuse_lossy_altium_export() {
         let source = r#"(kicad_symbol_lib (version 20231120) (generator "test")
diff --git a/crates/altium-codec/src/model.rs b/crates/altium-codec/src/model.rs
index da126fd..705aa81 100644
--- a/crates/altium-codec/src/model.rs
+++ b/crates/altium-codec/src/model.rs
@@ -104,7 +104,9 @@ pub enum Graphic {
     /// Connected line segments through `points` (mils).
     Polyline { points: Vec<[f64; 2]>, #[serde(default)] width: f64 },
     /// Axis-aligned rectangle (mils).
-    Rect { x1: f64, y1: f64, x2: f64, y2: f64, #[serde(default)] width: f64, #[serde(default)] filled: bool },
+    Rect { x1: f64, y1: f64, x2: f64, y2: f64, #[serde(default)] width: f64, #[serde(default)] filled: bool,
+        /// Preserve background versus outline fill through canonical JSON.
+        #[serde(default, skip_serializing_if = "Option::is_none")] fill_style: Option<String> },
     /// Circle (mils).
     Circle { cx: f64, cy: f64, r: f64, #[serde(default)] width: f64 },
     /// Arc, angles in degrees (mils).