diff -Naur jfsw-20210725_716e1e3/src/grpscan.c jfsw-20210725_716e1e3.patched/src/grpscan.c
--- jfsw-20210725_716e1e3/src/grpscan.c	2021-10-28 17:13:15.000000000 -0400
+++ jfsw-20210725_716e1e3.patched/src/grpscan.c	2021-10-29 02:06:21.962684518 -0400
@@ -35,6 +35,7 @@
     { "Registered Version",         0x7545319F, 47536148, 0, "sw.grp", NULL, NULL },
     { "Shareware Version",          0x08A7FA1F, 26056769, 0, "swshare.grp", NULL, NULL },
     { "Wanton Destruction (Addon)", 0xA9AAA7B7, 48698128, 0, "wt.grp", NULL, NULL },
+    { "Twin Dragon (Addon)", 0xe06cb6b4, 53480783, 0, "td.grp", NULL, NULL },
     { NULL, 0, 0, 0, NULL, NULL, NULL },
 };
 struct grpfile *foundgrps = NULL;