diff -r 45d0233e7d79 -r 187e3ef04cc9 src/newgrf_gui.cpp
--- a/src/newgrf_gui.cpp	Sat Mar 03 20:33:32 2007 +0000
+++ b/src/newgrf_gui.cpp	Sun Mar 04 04:25:36 2007 +0000
@@ -485,6 +485,9 @@
 			break;
 
 		case WE_DESTROY:
+			if (!WP(w, newgrf_d).execute) {
+				CopyGRFConfigList(WP(w, newgrf_d).orig_list, *WP(w, newgrf_d).list);
+			}
 			/* Remove the temporary copy of grf-list used in window */
 			ClearGRFConfigList(WP(w, newgrf_d).list);
 			break;