Heh, I first encountered this when I used the profit graphics settings while on a raid.
While there's an option on your persona screen to display cloaks this is overwritten by an option on the main options sceen under animation which is also a tick box for displaying cloaks.
I think somewhere along the line the way the options were selected has been altered and when u switch to one of the preset graphics setting it disables the tick box in the main options screen.
I'd suggest u check the option under animation...bet u anything it's unticked
