BeatKitano's post in Re-simmetrize partial object and navigation frame was marked as the answer
You can deactivate navi-frame in navigation preferences (at the bottom of the scrolling panel I think).
Note: hidding the frame doesn't change the hotzone I think (you may want to customize your navigation options to include (or not) the "Is In Nav Zone" option for that.
BeatKitano's post in Brush Rippling/Stepping was marked as the answer
Don't use buildup, go slow with steady stroke (I usualy do 15).
Some brushes behave beautifuly others... not. Buildup is one of the uglies. Try clay much better.
And if you want absolute control over your stroke use splines... in fact everyone should just use splines...