I played some more and found that the only thing that was missing in the tcl code was the line:
wm overrideredirect $wname on (where wname is the window name)
I was able to run the etcl demos of the calculator and the ataxx game after adding this line. I also created a launcher and then run nicely.
This means that existing Tk application with slight modification can run nicely on the kindle. of course the Etcl demos with the additional line need no further modification.