DOS ain't dead

I had installed HXRT217.zip under DOS7.1 and run the program sfk.exe, but it won't work. The sfk.exe is a part of the SwiftForth IDE environment, for Win32 console mode app development. (Its evaluation version can be download from http://www.forth.com/swiftforth/dl.html)

After running the HXLdr32.exe, the sfk can be started OK, but something is wrong. I can "emit" a character to the screen and get the key code pressed from the keyboard. But I can't define any single word(i.e. function), such as
: t1 1 ;
will get a "catch = -80" error.

I also compile a simple app foo.exe under XP's DOS Box. It prints a message on the screen and wait for a key press to exit this app. This program works fine under XP's Box, but fails in DOS7.1 with HXLdr32. I don't see any message on the screen and can't exit by pressing a key except the 'Enter'.

Any suggestions? How to 'debug' this kind of problem?

--Jach