The flint should be 1/16" or so away from the face of the frizzen. You may need to cut a hole in the leather to it can push back around the screw. Some folks advocate nibbling a notch out of the back of the flint to clear the screw also. Having the bevel up will move the cutting edge of the flint down a little and provide some clearance compared with bevel down. CVA should use a 5/8" flint, for what it's worth. That's the width, and you will probably want to select some which are as long.
For the trigger slop, you can solder (or use JB Weld) a piece of steel on top of it to bring it closer to the seer bar, or inlet the trigger plate deeper into the stock to lessen the clearance between the two.
Hope that helps!
~Kees~