locking unlocking constraints on a sketch I am using a great book, Parametric Modeling with Creo Parametric by Randy Shih.In one section (pg. 4-8), it talks about locking and unlocking constraints on a sketch.The book tells that by right clicking we can activate lock or unlock given constraints (L1, H, V etc.)Well, this would be great if I could get it to work, but I don't seem to get the same menu options when I do this. I also do not see the red circles that the book talks about. Is there some setting or version of Creo that doesn't allow this? I am using Creo 2.0 academic version.In general, it would be very nice if there were a way to see the pre-existing constraints on a drawing sketch. I have never been able to see this until I try to modify a sketch and it give me the violation window, where I then must choose to delete an existing constraint or live with the sketch as is.Is there any way to see and edit the existing constraints on a sketch?Thanks.