Without any system information we can't really tell you much, but based on how crammed your screenshot looks and how small the cropped region is, I would guess that your system does not meet the system requirements for screen resolution and/ or its hardware acceleration is inadequate because it's some kind of cheap notebook. With that in mind it seems inevitable that you run into problems with hardware accelerated functions like Perspective Warp. Short of fiddling with the relevant settings in the preferences, updating your graphics driver and tweaking its settings I don't think there's much you can do. anyway, just a guess of course. If you provide more info we may be able to advise further.