diff -r a05d111285d8 src/network.cpp
--- a/src/network.cpp Wed Mar 18 20:53:03 2015 -0400
+++ b/src/network.cpp Wed Mar 18 20:53:36 2015 -0400
@@ -466,12 +466,20 @@
                 // [TP] The wad that had this map is no longer optional.
                 Wads.LumpIsMandatory( mdata->lumpnum );
             }
+
+ // [CK] If the map was opened, clean up the memory.
+ if ( mdata )
+ delete mdata;
         }
         catch ( CRecoverableError& e )
         {
             // [TP] Might as well warn the user now that we're here.
             Printf( "NETWORK_Construct: \\cGWARNING: Cannot open map %s: %s\n",
                 info.mapname, e.GetMessage() );
+
+ // [CK] If the map was opened, clean up the memory.
+ if ( mdata )
+ delete mdata;
         }
     }
 
@@ -1073,6 +1081,9 @@
             sum.AppendFormat ("%02X", BSum[j]);
 
         longSum += sum;
+
+ // [CK] If the map was opened, clean up the memory.
+ delete mdata;
     }
 
     CMD5Checksum::GetMD5( reinterpret_cast<const BYTE *>( longSum.GetChars( ) ),