diff --git a/Source/Core/Controls/CheckboxArrayControl.cs b/Source/Core/Controls/CheckboxArrayControl.cs
index e9682cc..6f8db8c 100644
--- a/Source/Core/Controls/CheckboxArrayControl.cs
+++ b/Source/Core/Controls/CheckboxArrayControl.cs
@@ -71,15 +71,19 @@ namespace CodeImp.DoomBuilder.Controls
 			return c;
 		}
 
-        public void UpdateCheckboxes(IDictionary<string,string> newflags)
-        {
-            int i = 0;
-            foreach (KeyValuePair<string,string> p in newflags)
-            {
-                checkboxes[i].Text = p.Value;
-                i++;
-            }
-        }
+		public void UpdateCheckboxes(IDictionary<string,string> newflags, IDictionary<string, string> baseflags)
+		{
+		int i = 0;
+			foreach (KeyValuePair<string,string> p in newflags)
+			{
+				checkboxes[i].Text = p.Value;
+
+				baseflags.TryGetValue(p.Key, out string basevalue);
+				checkboxes[i].BackColor = (p.Value != basevalue) ? Color.LightGray : Color.White;
+
+				i++;
+			}
+		}
 
 		//mxd
 		public int GetWidth() 
diff --git a/Source/Core/Controls/ThingBrowserControl.cs b/Source/Core/Controls/ThingBrowserControl.cs
index 9b33457..d010904 100644
--- a/Source/Core/Controls/ThingBrowserControl.cs
+++ b/Source/Core/Controls/ThingBrowserControl.cs
@@ -371,6 +371,7 @@ namespace CodeImp.DoomBuilder.Controls
 					int offset = 2 + (int)g.MeasureString(parametercaption.Text, parametercaption.Font).Width;
 					parametercaption.Location = new System.Drawing.Point(Math.Max(60 - offset, 0), 27);
 					parametercaption.Size = new System.Drawing.Size(offset, 13);
+					parametercaption.BackColor = (parametercaption.Text != "Parameter:") ? Color.LightGray : Color.White;
 				}
 
 				if(doupdatenode)
diff --git a/Source/Core/Windows/LinedefEditForm.cs b/Source/Core/Windows/LinedefEditForm.cs
index f2939a1..8a70b38 100644
--- a/Source/Core/Windows/LinedefEditForm.cs
+++ b/Source/Core/Windows/LinedefEditForm.cs
@@ -339,7 +339,7 @@ namespace CodeImp.DoomBuilder.Windows
 				linedefprops.Add(new LinedefProperties(l));
 			}
 
-            if (allsameaction) flags.UpdateCheckboxes(newFlags);
+            if (allsameaction) flags.UpdateCheckboxes(newFlags, General.Map.Config.LinedefFlags);
 
             // Refresh controls so that they show their image
             backhigh.Refresh();
@@ -560,7 +560,7 @@ namespace CodeImp.DoomBuilder.Windows
 
                 LinedefActionInfo li = General.Map.Config.GetLinedefActionInfo(action.Value);
                 IDictionary<string, string> newFlags = (li == null || li.Flags.Count == 0) ? General.Map.Config.LinedefFlags : li.Flags;
-                flags.UpdateCheckboxes(newFlags);
+                flags.UpdateCheckboxes(newFlags, General.Map.Config.LinedefFlags);
 
 				// (Re)set hacky flat alignment 
 				foreach (Linedef l in lines)
diff --git a/Source/Core/Windows/ThingEditForm.cs b/Source/Core/Windows/ThingEditForm.cs
index ff116e7..80a4dfd 100644
--- a/Source/Core/Windows/ThingEditForm.cs
+++ b/Source/Core/Windows/ThingEditForm.cs
@@ -284,11 +284,12 @@ namespace CodeImp.DoomBuilder.Windows
 
             if (allsametype)
             {
-                flags.UpdateCheckboxes(newFlags);
+                flags.UpdateCheckboxes(newFlags, General.Map.Config.ThingFlags);
                 if (ti != null)
                 {
                     groupBox4.Text = ti.AngleText;
-                    label3.Text = ti.FlagsValueText + ":";
+					groupBox4.BackColor = (groupBox4.Text != "Angle") ? Color.LightGray : Color.White;
+					label3.Text = ti.FlagsValueText + ":";
                 }
             }
 
@@ -300,8 +301,9 @@ namespace CodeImp.DoomBuilder.Windows
 			flags_OnValueChanged(flags, EventArgs.Empty);
 			preventmapchange = false;
             flagsvalue.Text = evaluateFlagsValue();
+			label3.BackColor = (label3.Text != "Flags value:") ? Color.LightGray : Color.White;
 
-            argscontrol.UpdateScriptControls(); //mxd
+			argscontrol.UpdateScriptControls(); //mxd
 			actionhelp.UpdateAction(action.GetValue()); //mxd
 		}
 
@@ -635,11 +637,13 @@ namespace CodeImp.DoomBuilder.Windows
 			}
 
             IDictionary<string, string> newFlags = (thinginfo == null || thinginfo.Flags.Count == 0) ? General.Map.Config.ThingFlags : thinginfo.Flags;
-            flags.UpdateCheckboxes(newFlags);
+            flags.UpdateCheckboxes(newFlags, General.Map.Config.ThingFlags);
             groupBox4.Text = (thinginfo == null) ? "Angle" : thinginfo.AngleText;
+			groupBox4.BackColor = (groupBox4.Text != "Angle") ? Color.LightGray : Color.White;
             label3.Text = (thinginfo == null) ? "Flags value:" : thinginfo.FlagsValueText + ":";
+			label3.BackColor = (label3.Text != "Flags value:") ? Color.LightGray : Color.White;
 
-            General.Map.IsChanged = true;
+			General.Map.IsChanged = true;
 			if(OnValuesChanged != null) OnValuesChanged(this, EventArgs.Empty);
 		}