This didn't help...
Sluggish Brushes
This regression was introduced in CX 4.1. Brushes are sluggish to the point they don't draw smoothly. If you draw a circle, you get a straight line. One way to help is to turn off precise brushes. Edit -> Preferences -> Display & Cursors -> Paint Brushes -> Select the radio Standard. But this functionality is practically useless now - Joe
Any other suggestions?