Hi mir4ea, the Inset command is basically set up to generate a shape that has a border around it - if you want something with a 0 border width that would then be just a regular offset, use Offset or Shell for doing something like that rather than Inset.

Some previous discussion here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=5508.11

- Michael