Hi Axel
I was following this tutorial
https://sites.google.com/site/akohlmey/software/topotools/topotools-tutorial---part-1
the keywords I entered are
mol new chain.xyz autobonds no waitfor all
set sel [atomselect top all]
$sel set radius 0.85any guidance
it works for me. you must be doing something
wrong and ignore the error message or do a
bad cut'n'paste. i am not a magician.
axel.