I've just tried the sophiesew digitizing program, but I'm not able to figure out how to erase or delete a line I made on accident.  Do you know how to do that? 

Hi, I've just downloaded this program and been going through the tutorials, but I'm missing an important thing, I can't figure out how to erase a border I made.  I accidentally made a line outside the design and can't figure out how to erase it!!  If you can offer any assistance I would greatly appreciate it!!  Or anyone reading this, THANKS!!
I really like it so far, seem's fairly simple to use.