diff --git a/diylc/diylc-core/src/main/java/org/diylc/core/annotations/RequiredPositiveNonZeroMeasureValidator.java b/diylc/diylc-core/src/main/java/org/diylc/core/annotations/RequiredPositiveNonZeroMeasureValidator.java
new file mode 100644
index 000000000..e1cd215e1
--- /dev/null
+++ b/diylc/diylc-core/src/main/java/org/diylc/core/annotations/RequiredPositiveNonZeroMeasureValidator.java
@@ -0,0 +1,41 @@
+/*
+
+    DIY Layout Creator (DIYLC).
+    Copyright (c) 2009-2025 held jointly by the individual authors.
+
+    This file is part of DIYLC.
+
+    DIYLC is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    DIYLC is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with DIYLC.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+package org.diylc.core.annotations;
+
+import org.diylc.core.ValidationException;
+
+/**
+ * Same as {@link PositiveNonZeroMeasureValidator}, but also rejects an empty value. Use it for
+ * measures the component cannot be drawn without.
+ * 
+ * @author Branislav Stojkovic
+ */
+public class RequiredPositiveNonZeroMeasureValidator extends PositiveNonZeroMeasureValidator {
+
+  @Override
+  public void validate(Object owner, Object value) throws ValidationException {
+    if (value == null) {
+      throw new ValidationException("must not be empty.");
+    }
+    super.validate(owner, value);
+  }
+}
diff --git a/diylc/diylc-core/src/main/resources/update.xml b/diylc/diylc-core/src/main/resources/update.xml
index f091cccc9..fb25aec5d 100644
--- a/diylc/diylc-core/src/main/resources/update.xml
+++ b/diylc/diylc-core/src/main/resources/update.xml
@@ -637,6 +637,10 @@
 					<changeType>BUG_FIX</changeType>
 					<description>Rotated labels in pasted components and building blocks were drawn in the wrong place and at the wrong angle while following the mouse, until the components were placed</description>
 				</org.diylc.appframework.update.Change>
+				<org.diylc.appframework.update.Change>
+					<changeType>BUG_FIX</changeType>
+					<description>Projects with a resistor, capacitor or other leaded component whose Width or Length had been cleared in the property editor could not be opened; such values now fall back to the default size, and Width and Length can no longer be left empty</description>
+				</org.diylc.appframework.update.Change>
 			</changes>
 			<url>https://github.com/bancika/diy-layout-creator/releases</url>
 		</org.diylc.appframework.update.Version>
diff --git a/diylc/diylc-library/src/main/java/org/diylc/components/AbstractLeadedComponent.java b/diylc/diylc-library/src/main/java/org/diylc/components/AbstractLeadedComponent.java
index 5701ef43a..d0682aa77 100644
--- a/diylc/diylc-library/src/main/java/org/diylc/components/AbstractLeadedComponent.java
+++ b/diylc/diylc-library/src/main/java/org/diylc/components/AbstractLeadedComponent.java
@@ -45,7 +45,7 @@ import org.diylc.common.ObjectCache;
 import org.diylc.common.VerticalAlignment;
 import org.diylc.core.*;
 import org.diylc.core.annotations.EditableProperty;
-import org.diylc.core.annotations.PositiveNonZeroMeasureValidator;
+import org.diylc.core.annotations.RequiredPositiveNonZeroMeasureValidator;
 import org.diylc.core.measures.Size;
 import org.diylc.core.measures.SizeUnit;
 import org.diylc.presenter.CalcUtils;
@@ -637,8 +637,12 @@ public abstract class AbstractLeadedComponent<T> extends AbstractLabeledComponen
     this.borderColor = borderColor;
   }
 
-  @EditableProperty(name = "Length", defaultable = true, validatorClass = PositiveNonZeroMeasureValidator.class, sortOrder = 101)
+  @EditableProperty(name = "Length", defaultable = true, validatorClass = RequiredPositiveNonZeroMeasureValidator.class, sortOrder = 101)
   public Size getLength() {
+    // from 5.13 until this value became required, the property editor could clear it and files store null
+    if (length == null && getDefaultLength() != null) {
+      length = new Size(getDefaultLength().getValue(), getDefaultLength().getUnit());
+    }
     return length;
   }
 
@@ -672,8 +676,12 @@ public abstract class AbstractLeadedComponent<T> extends AbstractLabeledComponen
     }
   }
 
-  @EditableProperty(name = "Width", defaultable = true, validatorClass = PositiveNonZeroMeasureValidator.class, sortOrder = 102)
+  @EditableProperty(name = "Width", defaultable = true, validatorClass = RequiredPositiveNonZeroMeasureValidator.class, sortOrder = 102)
   public Size getWidth() {
+    // from 5.13 until this value became required, the property editor could clear it and files store null
+    if (width == null && getDefaultWidth() != null) {
+      width = new Size(getDefaultWidth().getValue(), getDefaultWidth().getUnit());
+    }
     return width;
   }