OK, I open acad (vanilla) clicked and held down over a corner and moved the mose around in circles for about 30 seconds causing many more than 5 different sizes. Repeated on the 3 remaining corners. Just in case I misunderstood, i did a click, resize, release, repeat, repeat, repeat, repeat, repeat as quickly as I could perform it. Acad didn't at any time lock up on me. If you've got anything else you'd like me to try, just let me know.