Difficulty with GPSIM and C code

I'm using GPSIM (version 0.22.0) and SDCC (version 2.9.0) in antiX Linux M8.2.

I'm going through the exercise in http://www.micahcarrick.com/04-25-2005/pic-c-programming-linux.html .  Everything seems OK when I run and step through the code except that I can't see the green arrow in the source browser for the C code, but I can see the port b1 arrow in the breadboard image alternate between red and green.

Is there some simple thing that I have configured incorrectly?  I can make a screenshot and send it to you individually if you're interested.  (I don't think I'm allowed to send attachments to this list, and I don't think most people would like it if I did.)

I'm hoping that one of you has resolved a situation like this before and can shed some light.  It's just one little thing - I can't see the arrow pointing to the line in the C code being executed.

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Jason Hsu, Linux user <[email protected]>