diff --git a/crates/idml/src/import.rs b/crates/idml/src/import.rs
index 9fd519efb..108df9430 100644
--- a/crates/idml/src/import.rs
+++ b/crates/idml/src/import.rs
@@ -499,10 +499,12 @@ impl<'r> Importer<'r> {
                     characters: c.get("CustomCharacters").unwrap_or("").into(),
                     family: c.prop("AppliedFont").unwrap_or_default(),
                     style: c.get("FontStyle").unwrap_or("Regular").trim_start_matches("$ID/").into(),
-                    relative_size: c.num("RelativeSize").unwrap_or(100.0) / 100.0,
-                    horizontal_scale: c.num("HorizontalScale").unwrap_or(100.0) / 100.0,
-                    vertical_scale: c.num("VerticalScale").unwrap_or(100.0) / 100.0,
-                    baseline_shift: c.num("BaselineShift").unwrap_or(0.0) / 100.0,
+                    // A metric `Document::check` refuses would make the whole file fail to
+                    // open, so one that is unusable here falls back to full size / no shift.
+                    relative_size: c.num("RelativeSize").filter(|v| v.is_finite() && *v > 0.0).unwrap_or(100.0) / 100.0,
+                    horizontal_scale: c.num("HorizontalScale").filter(|v| v.is_finite() && *v > 0.0).unwrap_or(100.0) / 100.0,
+                    vertical_scale: c.num("VerticalScale").filter(|v| v.is_finite() && *v > 0.0).unwrap_or(100.0) / 100.0,
+                    baseline_shift: c.num("BaselineShift").filter(|v| v.is_finite()).unwrap_or(0.0) / 100.0,
                     scale_option: c.boolean("ScaleOption").unwrap_or(true),
                 })
                 .collect();
@@ -531,9 +533,9 @@ impl<'r> Importer<'r> {
                             target_class: r.num("TargetMojikumiClass").unwrap_or(0.0) as i16,
                             side_class: r.num("SideMojikumiClass").unwrap_or(0.0) as i16,
                             after: r.boolean("SideIsAfterTarget").unwrap_or(false),
-                            minimum: r.num("Minimum").unwrap_or(0.0),
-                            desired: r.num("Desired").unwrap_or(0.0),
-                            maximum: r.num("Maximum").unwrap_or(0.0),
+                            minimum: r.num("Minimum").filter(|v| v.is_finite()).unwrap_or(0.0),
+                            desired: r.num("Desired").filter(|v| v.is_finite()).unwrap_or(0.0),
+                            maximum: r.num("Maximum").filter(|v| v.is_finite()).unwrap_or(0.0),
                             priority: r.num("CompressionPriority").unwrap_or(0.0) as i16,
                             does_not_float: r.boolean("AkiDoesNotFloat").unwrap_or(false),
                         })
diff --git a/crates/idml/src/tests.rs b/crates/idml/src/tests.rs
index 042a0c8d9..cc5067313 100644
--- a/crates/idml/src/tests.rs
+++ b/crates/idml/src/tests.rs
@@ -2443,6 +2443,32 @@ fn the_default_cjk_leading_model_applies_only_with_a_japanese_composer() {
     assert_eq!(model("$ID/HL Single J"), Some(designcraft_doc::cjk::LeadingModel::AkiBelow));
 }
 
+/// A composite-font or mojikumi metric `Document::check` refuses (zero, NaN, infinity) must
+/// not make the whole package fail to open: the entry falls back to a usable value instead.
+#[test]
+fn unusable_cjk_metrics_do_not_refuse_the_whole_file() {
+    let designmap = r#"<Document xmlns:idPkg="http://ns.adobe.com/AdobeInDesign/idml/1.0/packaging" Self="d">
+          <CompositeFont Self="cf" Name="Rubies">
+            <CompositeFontEntry Self="e1" Name="Dot" AppliedFont="Myriad Pro" RelativeSize="0"/>
+            <CompositeFontEntry Self="e2" Name="Bar" AppliedFont="Myriad Pro" BaselineShift="NaN"/>
+          </CompositeFont>
+          <MojikumiTable Self="mt" Name="Table">
+            <Properties><OverrideMojikumiAkiList>
+              <OverrideMojikumiAkiType Minimum="NaN" Desired="1" Maximum="2"/>
+            </OverrideMojikumiAkiList></Properties>
+          </MojikumiTable>
+          <idPkg:Spread src="Spreads/Spread_s.xml"/>
+        </Document>"#;
+    let spread = r#"<idPkg:Spread xmlns:idPkg="http://ns.adobe.com/AdobeInDesign/idml/1.0/packaging">
+          <Spread Self="s"><Page Self="p" GeometricBounds="0 0 100 100" ItemTransform="1 0 0 1 0 0"/></Spread>
+        </idPkg:Spread>"#;
+    let d = import_idml(&zip_files(&[("designmap.xml", &designmap), ("Spreads/Spread_s.xml", &spread)])).unwrap();
+    let entries = &d.styles.composite_fonts[0].entries;
+    assert_eq!(entries[0].relative_size, 1.0, "an unusable relative size falls back to full size");
+    assert_eq!(entries[1].baseline_shift, 0.0, "an unusable shift falls back to none");
+    assert_eq!(d.styles.mojikumi_tables[0].overrides[0].minimum, 0.0);
+}
+
 mod liquid_page_rules {
     use super::*;
     use designcraft_doc::LiquidRule as R;