lualoader: Tweak positioning and fix an off-by-one

lualoader: Tweak positioning and fix an off-by-one

- All of our default positions were offset from forth
- Our menu frame size was smaller than in forth
- Logo/brand drawing had an off-by-one, drawing one column lower on the
  screen than they should have been.
- While here, switch a print() to printc() as it's expected that logos may
  contain color and other escpae sequences that we'll need to honor.