Hi Anis - I would like to add an option in for Offset to add "caps" at the ends between the offset and the original, I think that would solve the problem you are showing there where you need to draw lines to connect the pieces when offsetting a curve that is not closed?

But actually if you want to clean up those corners, you don't really need to draw in those extra lines at all, just leave it like this:



Then select all the pieces (with no extra line drawn in):



Run Edit/Trim. At the prompt which says "Select cutting objects or Done for mutual trim", just right-click or push the Done button - this signals that you will be using all the pieces to cut each other.

Then at the "Select pieces to remove" prompt, select these bits:



And right-click or push Done to remove those and clean up that intersection:




If you are just going to trim away those areas, there is no need to draw an extra line there to connect the open offset pieces.

- Michael