Make the directory getting bit work with Win32 paths.

xtrn/dgnlance/dgnlance.js

 var startup_path='.';
 try { throw barfitty.bar.barf() } catch(e) { startup_path=e.fileName }
-startup_path=startup_path.replace(/\/[^\/]*$/,'');
+startup_path=startup_path.replace(/[\/\\][^\/\\]*$/,'');
 startup_path=backslash(startup_path);
 
 load("sbbsdefs.js");