diff --git a/src/modules/netinstall/PackageModel.cpp b/src/modules/netinstall/PackageModel.cpp
index beb094d2d..147bd5a5c 100644
--- a/src/modules/netinstall/PackageModel.cpp
+++ b/src/modules/netinstall/PackageModel.cpp
@@ -10,6 +10,7 @@
 
 #include "PackageModel.h"
 
+#include "utils/Logger.h"
 #include "utils/Variant.h"
 #include "utils/Yaml.h"
 
@@ -245,9 +246,21 @@ PackageModel::setupModelData( const QVariantList& groupList, PackageTreeItem* pa
                     }
                 }
             }
+            if ( !item->childCount() )
+            {
+                cWarning() << "*packages* under" << item->name() << "is empty.";
+            }
         }
         if ( groupMap.contains( "subgroups" ) )
         {
+            bool haveWarned = false;
+            const auto& subgroupValue = groupMap.value( "subgroups" );
+            if ( !subgroupValue.canConvert( QVariant::List ) )
+            {
+                cWarning() << "*subgroups* under" << item->name() << "is not a list.";
+                haveWarned = true;
+            }
+
             QVariantList subgroups = groupMap.value( "subgroups" ).toList();
             if ( !subgroups.isEmpty() )
             {
@@ -257,10 +270,22 @@ PackageModel::setupModelData( const QVariantList& groupList, PackageTreeItem* pa
                 // the checked-state -- do it manually.
                 item->updateSelected();
             }
+            else
+            {
+                if ( !haveWarned )
+                {
+                    cWarning() << "*subgroups* list under" << item->name() << "is empty.";
+                }
+            }
         }
         if ( item->isHidden() )
         {
             m_hiddenItems.append( item );
+            if ( !item->isSelected() )
+            {
+                cWarning() << "Item" << ( item->parentItem() ? item->parentItem()->name() : QString() ) << '.'
+                           << item->name() << "is hidden, but not selected.";
+            }
         }
         else
         {
diff --git a/src/modules/netinstall/netinstall.conf b/src/modules/netinstall/netinstall.conf
index f96da9a8e..a9243510b 100644
--- a/src/modules/netinstall/netinstall.conf
+++ b/src/modules/netinstall/netinstall.conf
@@ -178,10 +178,11 @@ label:
 #    the group's packages are installed. It will run after **each** package in
 #    the group is installed.
 #
-# If you set both *hidden* and *selected* for a group, you are basically
+# If you set both *hidden* and *selected* for a top-level group, you are
 # creating a "default" group of packages which will always be installed
-# in the user's system. Setting *hidden* to true without *selected*, or with
-# *selected* set to false, is kind of pointless.
+# in the user's system. Hidden selected subgroups are installed if their
+# parent is selected. Setting *hidden* to true without *selected*, or with
+# *selected* set to false, is kind of pointless and will generate a warning.
 #
 # The *pre-install* and *post-install* commands are **not** passed to
 # a shell; see the **packages** module configuration (i.e. `packages.conf`)
@@ -291,11 +292,13 @@ groups:
     #
     # The name of the internal subgroup doesn't matter -- it is hidden
     # from the user -- so we can give them all bogus names and
-    # descriptions, even the same name. Here, we use "bogus".
+    # descriptions, even the same name. Here, we use "Bogus". You
+    # can re-use the subgroup name, it doesn't really matter.
     #
     # Each internal subgroup is set to *hidden*, so it does not show up
     # as an entry in the list, and it is set to *selected*,
-    # so that if you select its parent subgroup.
+    # so that if you select its parent subgroup, the packages from
+    # the subgroup are selected with it and get installed.
     - name: IDE
       description: "Development Environment"
       selected: false